I just joined, so asking the question here... re: the topic thread on estimating the size of bitcoin transactional volume: https://bitcointalk.org/index.php?topic=167466

I'm trying to figure a way to estimate the dollar amount of non-speculative bitcoin transactions at any given moment.  It seems that knowing this and knowing the total number of bitcoins in circulation would provide a good way of calculating the expected current value of bitcoin.

i.e. using the equation  X/Y = Value of 1 bitcoin in USD in a given time interval; where X is the USD amount of bitcoin transactions for a given interval of time and Y is the number of coins in circulation

My first question is: Does this make sense?  I'm following the logic that the "actual" value of a bitcoin should be related to the total transactional volume flowing through the currency (check out this blog post for reference http://gruvr.com/blog/how-much-is-a-bitcoin-worth/comment-page-1/#comment-3352)

My second question is: Over what time interval should we look at the dollar amount of transactions?

Using the data in the thread I referenced, you could calculate:

116 million USD transactions per year / 11 million bitcoins = 10.5 USD/bitcoin over a year -- This would imply an average value for a bitcoin from April 2012 to April 2013; which is actually pretty consistent with the trading charts over that period of time (if you ignore the current bubble).

But... is this the right time-interval to look at?  If you take smaller time intervals, it implies smaller values for a bitcoin...

Curious everyone's thoughts on any and all of the above.