Everytime.
> console.log(h.percentile(NaN));
node[9818]: ../src/histogram-inl.h:37:double node::Histogram::Percentile(double): Assertion `(percentile) > (0)' failed.
1: 0x1012e4da5 node::Abort() (.cold.1) [/usr/local/bin/node]
2: 0x1000a6239 node::Abort() [/usr/local/bin/node]
3: 0x1000a60a1 node::Assert(node::AssertionInfo const&) [/usr/local/bin/node]
4: 0x10010f23f node::performance::(anonymous namespace)::ELDHistogramPercentile(v8::FunctionCallbackInfo<v8::Value> const&) [/usr/local/bin/node]
5: 0x10025a4e8 v8::internal::FunctionCallbackArguments::Call(v8::internal::CallHandlerInfo) [/usr/local/bin/node]
6: 0x100259a7c v8::internal::MaybeHandle<v8::internal::Object> v8::internal::(anonymous namespace)::HandleApiCallHelper<false>(v8::internal::Isolate*, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::FunctionTemplateInfo>, v8::internal::Handle<v8::internal::Object>, v8::internal::BuiltinArguments) [/usr/local/bin/node]
7: 0x1002591a2 v8::internal::Builtin_Impl_HandleApiCall(v8::internal::BuiltinArguments, v8::internal::Isolate*) [/usr/local/bin/node]
8: 0x100a7a359 Builtins_CEntry_Return1_DontSaveFPRegs_ArgvOnStack_BuiltinExit [/usr/local/bin/node]