diff --git a/package/gluon-announce/files/lib/gluon/announce/statistics.d/overlay b/package/gluon-announce/files/lib/gluon/announce/statistics.d/overlay
index 7dc6eed0f2fcae7e4431455d797549a12b0bd13c..6f1b7edf1eb53e449b8fc9ac5d1d018541dece4e 100644
--- a/package/gluon-announce/files/lib/gluon/announce/statistics.d/overlay
+++ b/package/gluon-announce/files/lib/gluon/announce/statistics.d/overlay
@@ -2,6 +2,8 @@ local fs = require "nixio.fs"
 local opkg = require "luci.model.ipkg"
 
 local st = fs.statvfs(opkg.overlay_root())
-local used = 100*((st.blocks - st.bfree) / st.blocks) or 0
+local blocks = st.blockss or 0
+local bfree = st.bfree or 0
+local used = ((blocks - bfree) / blocks)
 
 return math.floor(used * 1000 + 0.5) / 1000