diff --git a/parity/cli/mod.rs b/parity/cli/mod.rs
index a38d36d242d..855f28444a7 100644
--- a/parity/cli/mod.rs
+++ b/parity/cli/mod.rs
@@ -346,6 +346,7 @@ usage! {
 			ARG arg_password: (Vec<String>) = Vec::new(), or |c: &Config| otry!(c.account).password.clone(),
 			"--password=[FILE]...",
 			"Provide a file containing a password for unlocking an account. Leading and trailing whitespace is trimmed.",
+
 		["UI options"]
 			FLAG flag_force_ui: (bool) = false, or |c: &Config| otry!(c.ui).force.clone(),
 			"--force-ui",
@@ -696,6 +697,10 @@ usage! {
 			"--min-gas-price=[STRING]",
 			"Minimum amount of Wei per GAS to be paid for a transaction to be accepted for mining. Overrides --usd-per-tx.",
 
+			ARG arg_gas_price_percentile: (usize) = 50usize, or |c: &Config| otry!(c.mining).gas_price_percentile,
+			"--gas-price-percentile=[PCT]",
+			"Set PCT percentile gas price value from last 100 blocks as default gas price when sending transactions.",
+
 			ARG arg_author: (Option<String>) = None, or |c: &Config| otry!(c.mining).author.clone(),
 			"--author=[ADDRESS]",
 			"Specify the block author (aka \"coinbase\") address for sending block rewards from sealed blocks. NOTE: MINING WILL NOT WORK WITHOUT THIS OPTION.", // Sealing/Mining Option
@@ -1142,6 +1147,7 @@ struct Mining {
 	tx_time_limit: Option<u64>,
 	relay_set: Option<String>,
 	min_gas_price: Option<u64>,
+	gas_price_percentile: Option<usize>,
 	usd_per_tx: Option<String>,
 	usd_per_eth: Option<String>,
 	price_update_period: Option<String>,
@@ -1546,6 +1552,7 @@ mod tests {
 			arg_tx_time_limit: Some(100u64),
 			arg_relay_set: "cheap".into(),
 			arg_min_gas_price: Some(0u64),
+			arg_gas_price_percentile: 50usize,
 			arg_usd_per_tx: "0.0025".into(),
 			arg_usd_per_eth: "auto".into(),
 			arg_price_update_period: "hourly".into(),
@@ -1794,6 +1801,7 @@ mod tests {
 				work_queue_size: None,
 				relay_set: None,
 				min_gas_price: None,
+				gas_price_percentile: None,
 				usd_per_tx: None,
 				usd_per_eth: None,
 				price_update_period: Some("hourly".into()),
diff --git a/parity/configuration.rs b/parity/configuration.rs
index 1ab1ad7c04d..641f5cffa80 100644
--- a/parity/configuration.rs
+++ b/parity/configuration.rs
@@ -339,6 +339,7 @@ impl Configuration {
 				daemon: daemon,
 				logger_config: logger_config.clone(),
 				miner_options: self.miner_options()?,
+				gas_price_percentile: self.args.arg_gas_price_percentile,
 				ntp_servers: self.ntp_servers(),
 				ws_conf: ws_conf,
 				http_conf: http_conf,
@@ -1357,6 +1358,7 @@ mod tests {
 			daemon: None,
 			logger_config: Default::default(),
 			miner_options: Default::default(),
+			gas_price_percentile: 50,
 			ntp_servers: vec![
 				"0.parity.pool.ntp.org:123".into(),
 				"1.parity.pool.ntp.org:123".into(),
diff --git a/parity/rpc_apis.rs b/parity/rpc_apis.rs
index f2d97f892f0..e39b42352de 100644
--- a/parity/rpc_apis.rs
+++ b/parity/rpc_apis.rs
@@ -226,6 +226,7 @@ pub struct FullDependencies {
 	pub fetch: FetchClient,
 	pub remote: parity_reactor::Remote,
 	pub whisper_rpc: Option<::whisper::RpcFactory>,
+	pub gas_price_percentile: usize,
 }
 
 impl FullDependencies {
@@ -241,7 +242,7 @@ impl FullDependencies {
 			($namespace:ident, $handler:expr, $deps:expr, $nonces:expr) => {
 				{
 					let deps = &$deps;
-					let dispatcher = FullDispatcher::new(deps.client.clone(), deps.miner.clone(), $nonces);
+					let dispatcher = FullDispatcher::new(deps.client.clone(), deps.miner.clone(), $nonces, deps.gas_price_percentile);
 					if deps.signer_service.is_enabled() {
 						$handler.extend_with($namespace::to_delegate(SigningQueueClient::new(&deps.signer_service, dispatcher, deps.remote.clone(), &deps.secret_store)))
 					} else {
@@ -256,6 +257,7 @@ impl FullDependencies {
 			self.client.clone(),
 			self.miner.clone(),
 			nonces.clone(),
+			self.gas_price_percentile,
 		);
 		for api in apis {
 			match *api {
@@ -277,6 +279,7 @@ impl FullDependencies {
 							pending_nonce_from_queue: self.geth_compatibility,
 							allow_pending_receipt_query: !self.geth_compatibility,
 							send_block_number_in_get_work: !self.geth_compatibility,
+							gas_price_percentile: self.gas_price_percentile,
 						}
 					);
 					handler.extend_with(client.to_delegate());
@@ -422,6 +425,7 @@ pub struct LightDependencies<T> {
 	pub geth_compatibility: bool,
 	pub remote: parity_reactor::Remote,
 	pub whisper_rpc: Option<::whisper::RpcFactory>,
+	pub gas_price_percentile: usize,
 }
 
 impl<C: LightChainClient + 'static> LightDependencies<C> {
@@ -440,6 +444,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 			self.cache.clone(),
 			self.transaction_queue.clone(),
 			Arc::new(Mutex::new(dispatch::Reservations::with_pool(self.fetch.pool()))),
+			self.gas_price_percentile,
 		);
 
 		macro_rules! add_signing_methods {
@@ -477,6 +482,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						self.transaction_queue.clone(),
 						self.secret_store.clone(),
 						self.cache.clone(),
+						self.gas_price_percentile,
 					);
 					handler.extend_with(Eth::to_delegate(client.clone()));
 
@@ -492,6 +498,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						self.sync.clone(),
 						self.cache.clone(),
 						self.remote.clone(),
+						self.gas_price_percentile,
 					);
 					self.client.add_listener(
 						Arc::downgrade(&client.handler()) as Weak<::light::client::LightChainNotify>
@@ -521,6 +528,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						signer,
 						self.dapps_address.clone(),
 						self.ws_address.clone(),
+						self.gas_price_percentile,
 					).to_delegate());
 
 					if !for_generic_pubsub {
diff --git a/parity/run.rs b/parity/run.rs
index 369c63b5c7f..2d620c1e269 100644
--- a/parity/run.rs
+++ b/parity/run.rs
@@ -87,6 +87,7 @@ pub struct RunCmd {
 	pub daemon: Option<String>,
 	pub logger_config: LogConfig,
 	pub miner_options: MinerOptions,
+	pub gas_price_percentile: usize,
 	pub ntp_servers: Vec<String>,
 	pub ws_conf: rpc::WsConfiguration,
 	pub http_conf: rpc::HttpConfiguration,
@@ -358,6 +359,7 @@ fn execute_light(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) ->
 		geth_compatibility: cmd.geth_compatibility,
 		remote: event_loop.remote(),
 		whisper_rpc: whisper_factory,
+		gas_price_percentile: cmd.gas_price_percentile,
 	});
 
 	let dependencies = rpc::Dependencies {
@@ -761,6 +763,7 @@ pub fn execute(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) -> R
 		fetch: fetch.clone(),
 		remote: event_loop.remote(),
 		whisper_rpc: whisper_factory,
+		gas_price_percentile: cmd.gas_price_percentile,
 	});
 
 	let dependencies = rpc::Dependencies {
diff --git a/rpc/src/v1/helpers/dispatch.rs b/rpc/src/v1/helpers/dispatch.rs
index ec8e10a9a15..bd5137c2e3b 100644
--- a/rpc/src/v1/helpers/dispatch.rs
+++ b/rpc/src/v1/helpers/dispatch.rs
@@ -88,6 +88,7 @@ pub struct FullDispatcher<C, M> {
 	client: Arc<C>,
 	miner: Arc<M>,
 	nonces: Arc<Mutex<nonce::Reservations>>,
+	gas_price_percentile: usize,
 }
 
 impl<C, M> FullDispatcher<C, M> {
@@ -96,11 +97,13 @@ impl<C, M> FullDispatcher<C, M> {
 		client: Arc<C>,
 		miner: Arc<M>,
 		nonces: Arc<Mutex<nonce::Reservations>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		FullDispatcher {
 			client,
 			miner,
 			nonces,
+			gas_price_percentile,
 		}
 	}
 }
@@ -111,6 +114,7 @@ impl<C, M> Clone for FullDispatcher<C, M> {
 			client: self.client.clone(),
 			miner: self.miner.clone(),
 			nonces: self.nonces.clone(),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 }
@@ -148,7 +152,9 @@ impl<C: MiningBlockChainClient, M: MinerService> Dispatcher for FullDispatcher<C
 			used_default_from: request.from.is_none(),
 			to: request.to,
 			nonce,
-			gas_price: request.gas_price.unwrap_or_else(|| default_gas_price(&*self.client, &*self.miner)),
+			gas_price: request.gas_price.unwrap_or_else(|| {
+				default_gas_price(&*self.client, &*self.miner, self.gas_price_percentile)
+			}),
 			gas: request.gas.unwrap_or_else(|| self.miner.sensible_gas_limit()),
 			value: request.value.unwrap_or_else(|| 0.into()),
 			data: request.data.unwrap_or_else(Vec::new),
@@ -218,8 +224,8 @@ pub fn fetch_gas_price_corpus(
 				})
 			})
 			.map(move |prices| {
-				// produce a corpus from the vector, cache it, and return
-				// the median as the intended gas price.
+				// produce a corpus from the vector and cache it.
+				// It's later used to get a percentile for default gas price.
 				let corpus: ::stats::Corpus<_> = prices.into();
 				cache.lock().set_gas_price_corpus(corpus.clone());
 				corpus
@@ -258,6 +264,8 @@ pub struct LightDispatcher {
 	pub transaction_queue: Arc<RwLock<LightTransactionQueue>>,
 	/// Nonce reservations
 	pub nonces: Arc<Mutex<nonce::Reservations>>,
+	/// Gas Price percentile value used as default gas price.
+	pub gas_price_percentile: usize,
 }
 
 impl LightDispatcher {
@@ -271,6 +279,7 @@ impl LightDispatcher {
 		cache: Arc<Mutex<LightDataCache>>,
 		transaction_queue: Arc<RwLock<LightTransactionQueue>>,
 		nonces: Arc<Mutex<nonce::Reservations>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		LightDispatcher {
 			sync,
@@ -279,6 +288,7 @@ impl LightDispatcher {
 			cache,
 			transaction_queue,
 			nonces,
+			gas_price_percentile,
 		}
 	}
 
@@ -345,6 +355,7 @@ impl Dispatcher for LightDispatcher {
 		};
 
 		// fast path for known gas price.
+		let gas_price_percentile = self.gas_price_percentile;
 		let gas_price = match request_gas_price {
 			Some(gas_price) => Either::A(future::ok(with_gas_price(gas_price))),
 			None => Either::B(fetch_gas_price_corpus(
@@ -352,8 +363,8 @@ impl Dispatcher for LightDispatcher {
 				self.client.clone(),
 				self.on_demand.clone(),
 				self.cache.clone()
-			).and_then(|corp| match corp.median() {
-				Some(median) => Ok(*median),
+			).and_then(move |corp| match corp.percentile(gas_price_percentile) {
+				Some(percentile) => Ok(*percentile),
 				None => Ok(DEFAULT_GAS_PRICE), // fall back to default on error.
 			}).map(with_gas_price))
 		};
@@ -738,11 +749,11 @@ fn decrypt(accounts: &AccountProvider, address: Address, msg: Bytes, password: S
 }
 
 /// Extract the default gas price from a client and miner.
-pub fn default_gas_price<C, M>(client: &C, miner: &M) -> U256 where
+pub fn default_gas_price<C, M>(client: &C, miner: &M, percentile: usize) -> U256 where
 	C: MiningBlockChainClient,
 	M: MinerService,
 {
-	client.gas_price_corpus(100).median().cloned().unwrap_or_else(|| miner.sensible_gas_price())
+	client.gas_price_corpus(100).percentile(percentile).cloned().unwrap_or_else(|| miner.sensible_gas_price())
 }
 
 /// Convert RPC confirmation payload to signer confirmation payload.
diff --git a/rpc/src/v1/helpers/light_fetch.rs b/rpc/src/v1/helpers/light_fetch.rs
index 64f075b016d..d7436d8cdac 100644
--- a/rpc/src/v1/helpers/light_fetch.rs
+++ b/rpc/src/v1/helpers/light_fetch.rs
@@ -60,6 +60,8 @@ pub struct LightFetch {
 	pub sync: Arc<LightSync>,
 	/// The light data cache.
 	pub cache: Arc<Mutex<Cache>>,
+	/// Gas Price percentile
+	pub gas_price_percentile: usize,
 }
 
 /// Extract a transaction at given index.
@@ -203,6 +205,7 @@ impl LightFetch {
 			None => Either::B(self.account(from, id).map(|acc| acc.map(|a| a.nonce))),
 		};
 
+		let gas_price_percentile = self.gas_price_percentile;
 		let gas_price_fut = match req.gas_price {
 			Some(price) => Either::A(future::ok(price)),
 			None => Either::B(dispatch::fetch_gas_price_corpus(
@@ -210,8 +213,8 @@ impl LightFetch {
 				self.client.clone(),
 				self.on_demand.clone(),
 				self.cache.clone(),
-			).map(|corp| match corp.median() {
-				Some(median) => *median,
+			).map(move |corp| match corp.percentile(gas_price_percentile) {
+				Some(percentile) => *percentile,
 				None => DEFAULT_GAS_PRICE.into(),
 			}))
 		};
diff --git a/rpc/src/v1/impls/eth.rs b/rpc/src/v1/impls/eth.rs
index f9b684a3112..dc450afccb3 100644
--- a/rpc/src/v1/impls/eth.rs
+++ b/rpc/src/v1/impls/eth.rs
@@ -66,6 +66,8 @@ pub struct EthClientOptions {
 	pub allow_pending_receipt_query: bool,
 	/// Send additional block number when asking for work
 	pub send_block_number_in_get_work: bool,
+	/// Gas Price Percentile used as default gas price.
+	pub gas_price_percentile: usize,
 }
 
 impl EthClientOptions {
@@ -84,6 +86,7 @@ impl Default for EthClientOptions {
 			pending_nonce_from_queue: false,
 			allow_pending_receipt_query: true,
 			send_block_number_in_get_work: true,
+			gas_price_percentile: 50,
 		}
 	}
 }
@@ -338,7 +341,7 @@ impl<C, SN: ?Sized, S: ?Sized, M, EM> Eth for EthClient<C, SN, S, M, EM> where
 	}
 
 	fn gas_price(&self) -> Result<RpcU256> {
-		Ok(RpcU256::from(default_gas_price(&*self.client, &*self.miner)))
+		Ok(RpcU256::from(default_gas_price(&*self.client, &*self.miner, self.options.gas_price_percentile)))
 	}
 
 	fn accounts(&self, meta: Metadata) -> Result<Vec<RpcH160>> {
diff --git a/rpc/src/v1/impls/eth_pubsub.rs b/rpc/src/v1/impls/eth_pubsub.rs
index 795ed760c0f..e9919335c19 100644
--- a/rpc/src/v1/impls/eth_pubsub.rs
+++ b/rpc/src/v1/impls/eth_pubsub.rs
@@ -92,12 +92,14 @@ impl EthPubSubClient<LightFetch> {
 		sync: Arc<LightSync>,
 		cache: Arc<Mutex<Cache>>,
 		remote: Remote,
+		gas_price_percentile: usize,
 	) -> Self {
 		let fetch = LightFetch {
 			client,
 			on_demand,
 			sync,
-			cache
+			cache,
+			gas_price_percentile,
 		};
 		EthPubSubClient::new(Arc::new(fetch), remote)
 	}
diff --git a/rpc/src/v1/impls/light/eth.rs b/rpc/src/v1/impls/light/eth.rs
index 768fd4705fd..1929b1cb75c 100644
--- a/rpc/src/v1/impls/light/eth.rs
+++ b/rpc/src/v1/impls/light/eth.rs
@@ -62,6 +62,7 @@ pub struct EthClient<T> {
 	accounts: Arc<AccountProvider>,
 	cache: Arc<Mutex<LightDataCache>>,
 	polls: Mutex<PollManager<PollFilter>>,
+	gas_price_percentile: usize,
 }
 
 impl<T> Clone for EthClient<T> {
@@ -75,6 +76,7 @@ impl<T> Clone for EthClient<T> {
 			accounts: self.accounts.clone(),
 			cache: self.cache.clone(),
 			polls: Mutex::new(PollManager::new()),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 }
@@ -89,15 +91,17 @@ impl<T: LightChainClient + 'static> EthClient<T> {
 		transaction_queue: Arc<RwLock<TransactionQueue>>,
 		accounts: Arc<AccountProvider>,
 		cache: Arc<Mutex<LightDataCache>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		EthClient {
-			sync: sync,
-			client: client,
-			on_demand: on_demand,
-			transaction_queue: transaction_queue,
-			accounts: accounts,
-			cache: cache,
+			sync,
+			client,
+			on_demand,
+			transaction_queue,
+			accounts,
+			cache,
 			polls: Mutex::new(PollManager::new()),
+			gas_price_percentile,
 		}
 	}
 
@@ -108,6 +112,7 @@ impl<T: LightChainClient + 'static> EthClient<T> {
 			on_demand: self.on_demand.clone(),
 			sync: self.sync.clone(),
 			cache: self.cache.clone(),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 
@@ -239,7 +244,7 @@ impl<T: LightChainClient + 'static> Eth for EthClient<T> {
 
 	fn gas_price(&self) -> Result<RpcU256> {
 		Ok(self.cache.lock().gas_price_corpus()
-			.and_then(|c| c.median().cloned())
+			.and_then(|c| c.percentile(self.gas_price_percentile).cloned())
 			.map(RpcU256::from)
 			.unwrap_or_else(Default::default))
 	}
diff --git a/rpc/src/v1/impls/light/parity.rs b/rpc/src/v1/impls/light/parity.rs
index 1be734df444..925919e5de0 100644
--- a/rpc/src/v1/impls/light/parity.rs
+++ b/rpc/src/v1/impls/light/parity.rs
@@ -60,6 +60,7 @@ pub struct ParityClient {
 	dapps_address: Option<Host>,
 	ws_address: Option<Host>,
 	eip86_transition: u64,
+	gas_price_percentile: usize,
 }
 
 impl ParityClient {
@@ -74,6 +75,7 @@ impl ParityClient {
 		signer: Option<Arc<SignerService>>,
 		dapps_address: Option<Host>,
 		ws_address: Option<Host>,
+		gas_price_percentile: usize,
 	) -> Self {
 		ParityClient {
 			light_dispatch,
@@ -85,7 +87,8 @@ impl ParityClient {
 			dapps_address,
 			ws_address,
 			eip86_transition: client.eip86_transition(),
-			client: client,
+			client,
+			gas_price_percentile,
 		}
 	}
 
@@ -96,6 +99,7 @@ impl ParityClient {
 			on_demand: self.light_dispatch.on_demand.clone(),
 			sync: self.light_dispatch.sync.clone(),
 			cache: self.light_dispatch.cache.clone(),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 }
diff --git a/rpc/src/v1/tests/eth.rs b/rpc/src/v1/tests/eth.rs
index 27b98f7f55f..bd39ccf06ae 100644
--- a/rpc/src/v1/tests/eth.rs
+++ b/rpc/src/v1/tests/eth.rs
@@ -153,7 +153,7 @@ impl EthTester {
 
 		let reservations = Arc::new(Mutex::new(nonce::Reservations::new()));
 
-		let dispatcher = FullDispatcher::new(client.clone(), miner_service.clone(), reservations);
+		let dispatcher = FullDispatcher::new(client.clone(), miner_service.clone(), reservations, 50);
 		let eth_sign = SigningUnsafeClient::new(
 			&opt_account_provider,
 			dispatcher,
diff --git a/rpc/src/v1/tests/mocked/eth.rs b/rpc/src/v1/tests/mocked/eth.rs
index 209d55127fb..504cef43a01 100644
--- a/rpc/src/v1/tests/mocked/eth.rs
+++ b/rpc/src/v1/tests/mocked/eth.rs
@@ -93,11 +93,12 @@ impl EthTester {
 		let snapshot = snapshot_service();
 		let hashrates = Arc::new(Mutex::new(HashMap::new()));
 		let external_miner = Arc::new(ExternalMiner::new(hashrates.clone()));
+		let gas_price_percentile = options.gas_price_percentile;
 		let eth = EthClient::new(&client, &snapshot, &sync, &opt_ap, &miner, &external_miner, options).to_delegate();
 		let filter = EthFilterClient::new(client.clone(), miner.clone()).to_delegate();
 		let reservations = Arc::new(Mutex::new(nonce::Reservations::new()));
 
-		let dispatcher = FullDispatcher::new(client.clone(), miner.clone(), reservations);
+		let dispatcher = FullDispatcher::new(client.clone(), miner.clone(), reservations, gas_price_percentile);
 		let sign = SigningUnsafeClient::new(&opt_ap, dispatcher).to_delegate();
 		let mut io: IoHandler<Metadata> = IoHandler::default();
 		io.extend_with(eth);
diff --git a/rpc/src/v1/tests/mocked/personal.rs b/rpc/src/v1/tests/mocked/personal.rs
index ce74ae686f6..fd0825f2849 100644
--- a/rpc/src/v1/tests/mocked/personal.rs
+++ b/rpc/src/v1/tests/mocked/personal.rs
@@ -56,7 +56,7 @@ fn setup() -> PersonalTester {
 	let miner = miner_service();
 	let reservations = Arc::new(Mutex::new(nonce::Reservations::new()));
 
-	let dispatcher = FullDispatcher::new(client, miner.clone(), reservations);
+	let dispatcher = FullDispatcher::new(client, miner.clone(), reservations, 50);
 	let personal = PersonalClient::new(opt_accounts, dispatcher, false);
 
 	let mut io = IoHandler::default();
@@ -112,7 +112,7 @@ fn invalid_password_test(method: &str)
 			"value": "0x9184e72a"
 		}, "password321"],
 		"id": 1
-	}"#;	
+	}"#;
 
 	let response = r#"{"jsonrpc":"2.0","error":{"code":-32021,"message":"Account password is invalid or account does not exist.","data":"SStore(InvalidPassword)"},"id":1}"#;
 
diff --git a/rpc/src/v1/tests/mocked/signer.rs b/rpc/src/v1/tests/mocked/signer.rs
index 2fb95a1d640..b21a06e2d60 100644
--- a/rpc/src/v1/tests/mocked/signer.rs
+++ b/rpc/src/v1/tests/mocked/signer.rs
@@ -65,7 +65,7 @@ fn signer_tester() -> SignerTester {
 	let reservations = Arc::new(Mutex::new(nonce::Reservations::new()));
 	let event_loop = EventLoop::spawn();
 
-	let dispatcher = FullDispatcher::new(client, miner.clone(), reservations);
+	let dispatcher = FullDispatcher::new(client, miner.clone(), reservations, 50);
 	let mut io = IoHandler::default();
 	io.extend_with(SignerClient::new(&opt_accounts, dispatcher, &signer, event_loop.remote()).to_delegate());
 
diff --git a/rpc/src/v1/tests/mocked/signing.rs b/rpc/src/v1/tests/mocked/signing.rs
index 8a6a790f8ed..81dd1f90f45 100644
--- a/rpc/src/v1/tests/mocked/signing.rs
+++ b/rpc/src/v1/tests/mocked/signing.rs
@@ -61,7 +61,7 @@ impl Default for SigningTester {
 		let reservations = Arc::new(Mutex::new(nonce::Reservations::new()));
 		let mut io = IoHandler::default();
 
-		let dispatcher = FullDispatcher::new(client.clone(), miner.clone(), reservations);
+		let dispatcher = FullDispatcher::new(client.clone(), miner.clone(), reservations, 50);
 
 		let remote = Remote::new_thread_per_future();
 
diff --git a/util/stats/src/lib.rs b/util/stats/src/lib.rs
index 01c988232fd..74fda927265 100644
--- a/util/stats/src/lib.rs
+++ b/util/stats/src/lib.rs
@@ -46,6 +46,18 @@ impl<T> Deref for Corpus<T> {
 }
 
 impl<T: Ord> Corpus<T> {
+	/// Get given percentile (approximated).
+	pub fn percentile(&self, val: usize) -> Option<&T> {
+		let len = self.0.len();
+		let x = val * len / 100;
+		let x = ::std::cmp::min(x, len);
+		if x == 0 {
+			return None;
+		}
+
+		self.0.get(x - 1)
+	}
+
 	/// Get the median element, if it exists.
 	pub fn median(&self) -> Option<&T> {
 		self.0.get(self.0.len() / 2)
@@ -121,7 +133,19 @@ impl<T: Ord + Copy + ::std::fmt::Display> Histogram<T>
 
 #[cfg(test)]
 mod tests {
-	use super::Histogram;
+	use super::*;
+
+	#[test]
+	fn check_corpus() {
+		let corpus = Corpus::from(vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
+		assert_eq!(corpus.percentile(0), None);
+		assert_eq!(corpus.percentile(1), None);
+		assert_eq!(corpus.percentile(101), Some(&10));
+		assert_eq!(corpus.percentile(100), Some(&10));
+		assert_eq!(corpus.percentile(50), Some(&5));
+		assert_eq!(corpus.percentile(60), Some(&6));
+		assert_eq!(corpus.median(), Some(&6));
+	}
 
 	#[test]
 	fn check_histogram() {