Is it true that you get about 0.7 for every watt on a HPS???

Hey everyone,
I saw a thread on this site that said for every watt on a HPS light you would get 0.7 worth of bud.

So lets say I have a 140 watt HPS, would this mean I'd get around 98 grams???

Thanks

yes but i think this only applies to 1000k lighting. its suppose to be 1gpw but depending on the grower .7 is average.

98g off a 140watt? how many plants do you have, cus with 140watts you're not gonna get much, its gonna be fluffy.

140watts isnt enough for more than a few plants considering you want between 50-100watt/square foot. i highly doubt those 3 plants would yield more than a half ounce each. im basing this off when my buddy grew some clones using a 250watt and didnt get more than a quarter/plant. 140watts just isnt enough to produce dense buds.