Average ten minute windspeed HTML tag?

I assumed that %avtenminutewind% was the tag containing the value shown as 'Average windspeed (ten minute) on the default WD web page. However this gives a different value, sometimes higher and sometimes lower, to the one shown on the default page generated at the same time. I can’t find any other tag which gives the same value as the one on the default web page.

Does anyone know what this tag is called or is the value not provided?

thats the one to use, but i have just check the code, and i was round the 10 minte averae (but not for the default graph routine)
i have changed that now, for the next version