diff --git a/WELA.ps1 b/WELA.ps1
index 52ffa52e..e6e7d3b5 100644
--- a/WELA.ps1
+++ b/WELA.ps1
@@ -72,7 +72,8 @@ function CalculateUsableRate {
     $totalCounts | ForEach-Object {
         $level = $_.Level
         $total = $_.Count
-        $usableCount = ($counts | Where-Object Level -eq $level | Select-Object -ExpandProperty Count -First 1) -or 0
+        $usableCount = ($counts | Where-Object Level -eq $level | Select-Object -ExpandProperty Count -First 1)
+        if ($null -eq $usableCount) { $usableCount = 0 }
         $percentage = if ($total -ne 0) { "{0:N2}" -f ($usableCount / $total * 100) } else { "0.00" }
         $result += [PSCustomObject]@{
             Level = $level