#### sjw

##### Well-known member

My course has a front 9 CR of 35 and a slope of 123. I shot a 44 which gives a differential of 8.3. I can work this much out through the usual calculation of 113/slope * (adj gross - CR), and it agrees with what I see on EG.

However, I have four differentials on my record so far - [18.4, 21.1, 8.3*, 18.4] - and I have an index of 16.4 (18.4-2)

I would have expected that the 8.3 would stand a chance of being the lowest differential. I'm sure it's not as simple as doubling it, but I can't work out a) why my handicap is still best-2 when I have four scores in and b) where the 8.3 fits in.

I am guessing that I

*don't*have four scores in technically because they're not all 18-hole differentials?

Now, as for the 8.3, I think I've read something about the 9-hole to 18-hole conversion does something like assume that I scored nett par on the "back 9" or something. Seeing as I didn't have a handicap at the time, presumably this means that the differential is something mahoosive? If it is, and you can put in 6*9-hole cards for your initial handicap, are some people going to end up with really high indexes at first?

According to EG, for that 9-hole round, I had a course handicap of 27, so I'm doing something along the lines of

113/123 * (44 + 35 + 54 +1 - 70) = 58.8

Which seems crazy given I shot 9 over CR through 9...