Index, Match Help

[dramey1]

hello, I'm struggling coming up with a formula to give me a value with 2 given starting conditions. I will paste my table in here after I explain it. So, the top row of data is a given number but not exact, and the various rows of numbers below the top row is also given, but not exact. The top row is rainfall rates, and the bulk of numbers is square feet. I need an equation that is able to find the correct column based off of the rainfall rate, and the correct row based off of the square feet, and then return the diameter needed from the left most column. The square feet will almost never be exact, and I need the equation to find the value that is greater than or equal to the given square feet. An equation or vba code will work fine with me. Thanks in advance.
[TABLE="width: 880"]
<colgroup><col span="3"><col><col span="2"><col><col><col><col span="4"></colgroup><tbody>[TR]
[TD][/TD]
[TD]1[/TD]
[TD]2[/TD]
[TD]3[/TD]
[TD]4[/TD]
[TD]5[/TD]
[TD]6[/TD]
[TD]7[/TD]
[TD]8[/TD]
[TD]9[/TD]
[TD]10[/TD]
[TD]11[/TD]
[TD]12[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]2880[/TD]
[TD]1440[/TD]
[TD]960[/TD]
[TD]720[/TD]
[TD]575[/TD]
[TD]480[/TD]
[TD]410[/TD]
[TD]360[/TD]
[TD]320[/TD]
[TD]290[/TD]
[TD]260[/TD]
[TD]240[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]8800[/TD]
[TD]4400[/TD]
[TD]2930[/TD]
[TD]2200[/TD]
[TD]1760[/TD]
[TD]1470[/TD]
[TD]1260[/TD]
[TD]1100[/TD]
[TD]980[/TD]
[TD]880[/TD]
[TD]800[/TD]
[TD]730[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]18400[/TD]
[TD]9200[/TD]
[TD]6130[/TD]
[TD]4600[/TD]
[TD]3680[/TD]
[TD]3070[/TD]
[TD]2630[/TD]
[TD]2300[/TD]
[TD]2045[/TD]
[TD]1840[/TD]
[TD]1675[/TD]
[TD]1530[/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD]34600[/TD]
[TD]17300[/TD]
[TD]11530[/TD]
[TD]8650[/TD]
[TD]6920[/TD]
[TD]5765[/TD]
[TD]4945[/TD]
[TD]4325[/TD]
[TD]3845[/TD]
[TD]3460[/TD]
[TD]3145[/TD]
[TD]2880[/TD]
[/TR]
[TR]
[TD]6[/TD]
[TD]54000[/TD]
[TD]27000[/TD]
[TD]17995[/TD]
[TD]13500[/TD]
[TD]10800[/TD]
[TD]9000[/TD]
[TD]7715[/TD]
[TD]6750[/TD]
[TD]6000[/TD]
[TD]5400[/TD]
[TD]4910[/TD]
[TD]4500[/TD]
[/TR]
[TR]
[TD]8[/TD]
[TD]116000[/TD]
[TD]58000[/TD]
[TD]38660[/TD]
[TD]29000[/TD]
[TD]23200[/TD]
[TD]19315[/TD]
[TD]16570[/TD]
[TD]14500[/TD]
[TD]12890[/TD]
[TD]11600[/TD]
[TD]10545[/TD]
[TD]9600[/TD]
[/TR]
</tbody>[/TABLE]

 

[dramey1]

I am trying to make as few changes to our data as possible. This is a spreadsheet for an entire office, and I want it to be easily understood. Thanks for the tip though.