Petals Around the Rose: Fraternity Register

I created a spreadsheet and had recorded 20 rolls of the dice and the corresponding answer, looking for patterns including the sum, median, average, high/low values, etc. The only progress I made was that I noticed that each answer was an even number. Then I went back and rolled a few more without recording or analyzing the result and it hit me. Actually, I'm quite surprised I got it that quickly.