Weighing jacket potatoes before or after cooking?

helcart01

I have always weighed my potato before cooking it and calculated my calories on that. The description I use is 'British White - Small Jacket Potato ( Home Baked )'. However today I weighed it before as usual and then after out of interest. There was a difference of 2.5 oz. Which weight should I use with this description? It only makes a difference of 33 cals but everyone on here emphasises the importance of accuracy.