diff --git a/misc/vim/syntax/factor.vim b/misc/vim/syntax/factor.vim
index c607472272..0f9e396ac9 100644
--- a/misc/vim/syntax/factor.vim
+++ b/misc/vim/syntax/factor.vim
@@ -69,7 +69,7 @@ syn cluster factorReal          contains=factorInt,factorFloat,factorPosRatio,fa
 syn cluster factorNumber        contains=@factorReal,factorComplex
 syn cluster factorNumErr        contains=factorBinErr,factorHexErr,factorOctErr
 syn match   factorInt           /\<-\=[0-9]\([0-9,]*[0-9]\)\?\([eE][+-][0-9]\+\)\?\>/
-syn match   factorFloat         /\<-\=[0-9]\([0-9,]*[0-9]\)\?\.[0-9,]*[0-9]\+\([eE][+-][0-9]\+\)\?\>/
+syn match   factorFloat         /\<-\=[0-9]\([0-9,]*[0-9]\)\?\(\.\([0-9,]*[0-9]\+\([eE][+-][0-9]\+\)\?\)\?\)\?\>/
 syn match   factorPosRatio      /\<+\=[0-9]\([0-9,]*[0-9]\)\?\(+[0-9]\([0-9,]*[0-9]\+\)\?\)\?\/-\=[0-9]\([0-9,]*[0-9]\+\)\?\.\?\>/
 syn match   factorNegRatio      /\<\-[0-9]\([0-9,]*[0-9]\)\?\(\-[0-9]\([0-9,]*[0-9]\+\)\?\)\?\/-\=[0-9]\([0-9,]*[0-9]\+\)\?\.\?\>/
 syn region  factorComplex       start=/\<C{\>/ end=/\<}\>/ contains=@factorReal