you know Los Angeles and San Francisco are very different markets and in Los Angeles in particular you know there may be a very large cost to pulling drivers from you know that look available from further away to come pick up a ride and that ride you know that cost as part of a distance dependent so these kinds of things you know it's often a question that comes up here is well why is this also not a matter of manipulation not just a multiplier on type on top of a formula but why not actually just directly be sort of manipulating prices