Good morning --
I'm trying to write an array formula that computes the minimum ratio between
one number and the sum of several columns, across about 50 rows of data. I
want to avoid problems that could occur when either the numerator or
denominator doesn't exist (because the user hasn't acquired that much data
yet). I got it to work checking to see if the denominator exists, with this
formula, which appeared to work:

{=MIN(IF(SUM('Practice Data'!$M$6:$V$53)<0,'Practice
Data'!$AI$6:$AI$53/SUM('Practice Data'!$M$6:$V$53),""))}

However, when I tried to check to see if the numerator existed as well, I
got a #VALUE! returned. Here's the offending formula:

{=MIN(IF(AND('Practice Data'!$AI$6:$AI$53<0,SUM('Practice
Data'!$M$6:$V$53)<0),'Practice Data'!$AI$6:$AI$53/SUM('Practice
Data'!$M$6:$V$53),""))}

Thanks in advance.