From

Location

Message

Date Posted

Watlington, UK

Hello all, is there a formula I can use on my spreadsheet which will convert OTT into pounds? I can use the charts manually of course but I would much prefer it to be automated via the spreadsheet.

7/22/2019 3:13:34 PM

Upa Creek, Mo

If you have the chart in spreadsheet form, you could just add a vlookup formula from the ott you enter to find the corresponding weight.

7/22/2019 3:56:44 PM

Westmoreland, KS

send me your email and i'll send you an excel file

7/22/2019 4:27:52 PM

Westmoreland, KS

I emailed it to you...it is close not perfect but pretty darn good.

7/22/2019 4:30:41 PM

Watlington, UK

Thanks both, I thought there would be a 'one fits all' simple formula but using a vlookup via a datasheet will work just as well

7/23/2019 7:36:49 AM

Algoma, Wisconsin

Can I get that too!

7/23/2019 8:01:33 AM

Upa Creek, Mo

If anyone needs help with the vlookup, just email me the ott chart in Excel (I don't have one), and I will send back with formula in it.

7/23/2019 8:27:50 AM

Westmoreland, KS

vlookup...I didn't know you were a computer nerd Luke!

7/23/2019 9:12:58 AM

Upa Creek, Mo

Haha

7/23/2019 10:34:43 AM

Eastern Pennsylvania

The BigPumpkins iPhone app has an OTT calculator built into the diary entry section. I don’t knew how current it is but it’s all hypothetical anyways.

7/23/2019 11:44:07 AM

Winnipeg, Manitoba

I made a nice one in excel last year. Send me an email and I'll gladly send it your way.

http://www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=294811

And here's the 2017 formula to convert OTT to pounds :

(((14.2/(1+7.3*2^(-(OTT)/96)))^3+((OTT)/51)^2.91)-8)*0.993

7/23/2019 2:22:32 PM

Winnipeg, Manitoba

I am thinking of making the same excel calculator for watermelons (it will be green of course - ha). I just don't have the formula for that one.

7/23/2019 2:25:47 PM

Eastern Pennsylvania

I’ve been under the assumption that the newer GPC charts are based on empirical data rather than a formula at this point. There certainly is enough data from our weigh offs. Is that not the case?

7/23/2019 9:41:19 PM

Winnipeg, Manitoba

Perhaps for the newer charts it's based on empirical data, I'm not sure. The GPC chart for Atlantic giants was still based by formula as of 2017 - it's listed below the chart.

https://gpc1.org/wp-content/uploads/2019/02/chartscombined2017.pdf

7/23/2019 10:34:50 PM

Pittsburgh, PA

I use the formula on the 2017 chart in an excel spreadsheet and it works perfectly.

7/23/2019 11:26:39 PM

Willamette Valley, Oregon

I'll confirm that that's the correct and current formula for the GPC OTT to weight chart.

It is calculated from the actual data (individual pumpkin weights and OTTs) so it's fair to call it empirical (as opposed to theoretical); and it's also a formula. - so it's both.
All past charts that I know of have been calculated this way too, so it's not a new method, but the accuracy is improved and bias minimized in the latest version.

8/6/2019 4:14:57 PM