@Base = (SELECT cntr_value FROM sys.dm_os_performance_counters
WHERE object_name = 'SQLServer:Buffer Manager'
AND counter_name = 'Buffer cache hit ratio base')
p1.object_name, p1.counter_name, p1.instance_name, RTRIM(p1.cntr_value / @Base) as 'Percent'FROM
sys.dm_os_performance_counters p1 WHERE p1.counter_name = 'Buffer cache hit ratio' and p1.object_name = 'SQLServer:Buffer Manager'
That will give you the percent for your Buffer Cache hit ratio...basically the Buffer cache hit ratio is divided by it's base to get the percentage.