diff --git a/check_time_machine_currency.sh b/check_time_machine_currency.sh
index 8123de0..3e91fd4 100755
--- a/check_time_machine_currency.sh
+++ b/check_time_machine_currency.sh
@@ -53,11 +53,12 @@ then
     exit 3
 fi
 
-# Check to see if we're running Mavericks as Time Machine runs a little differently
-osVersion=`sw_vers -productVersion | grep -E -o "[0-9]+\.[0-9]"`
+# Check to see if we're running Mavericks or Yosemite as Time Machine runs a little differently
+osVersion=`sw_vers -productVersion | grep -E -o "[0-9]+\.[0-9]?[0-9]"`
 isMavericks=`echo $osVersion '< 10.9' | bc -l`
+isYosemite=`echo $osVersion '< 10.10' | bc -l`
 
-if [ $isMavericks -eq 0 ]
+if [ $isMavericks -eq 0 ] || [ $isYosemite -eq 0 ]
 then
     # 10.9+ Check
     lastBackupDateString=`tmutil latestbackup | grep -E -o "[0-9]{4}-[0-9]{2}-[0-9]{2}-[0-9]{6}"`
@@ -105,4 +106,4 @@ then
 else
     printf "CRITICAL - Could not determine the last backup date for this Mac.\n"
     exit 2
-fi
\ No newline at end of file
+fi