diff --git a/vmstat.8 b/vmstat.8
index 8d48b499..ee8eaf5e 100644
--- a/vmstat.8
+++ b/vmstat.8
@@ -122,8 +122,8 @@ so: Amount of memory swapped to disk (/s).
 .SS
 .B "IO"
 .nf
-bi: Blocks received from a block device (blocks/s).
-bo: Blocks sent to a block device (blocks/s).
+bi: Kibibyte received from a block device (KiB/s).
+bo: Kibibyte sent to a block device (KiB/s).
 .fi
 .PP
 .SS