diff --git a/mempool/estimatefee.go b/mempool/estimatefee.go
index 53933469..3546f6b3 100644
--- a/mempool/estimatefee.go
+++ b/mempool/estimatefee.go
@@ -47,7 +47,7 @@ const (
 
 	bytePerKb = 1000
 
-	btcPerSatoshi = 1E-8
+	btcPerSatoshi = 1e-8
 )
 
 var (