Is there a way to calculate the buffer hit ratio for an individual SQL statement

 Background:

A predecessor put a process in place that reports the 'top 5 SQL statements' for the last 24 hours.   They used  (verbatim)  a process they pulled from the interwebs (if it's on the internet it must be true right?).  

 The script reports the SQL statement and the following stats:

:           Disk           Buffer Cache Hit                 DR Per      BG Per        CPU Per        Ela Per

:           Reads            Gets     Ratio       Runs         Run         Run            Run            Run

:           -----          ------ ---------       ----      ------      ------         ------         ------

:     235,970,373     236,773,166     0.34%        735     321,048     322,140           3.35          56.27

:       (54.168%)        (2.352%)

Well the .34% cache hit ratio has raised some flags (did I mention this report was forwarded to the director?).    The calculation they are using for the BCHR is: