Note: Figures are average daily homes passed over preceding year
These figures are based on numbers for total homes passed over time from RVA (the research firm of choice for the North American FTTH Council). As you can see, the pace of roll-out peaked in September 2008, and has been falling ever since, bar a slight up-tick in the year to March 2012, which RVA attributes to the combination of stimulus funds and a mild winter. The rate of deployment is now roughly 40% that at the peak.
Is this because FTTH coverage is already widespread? Not exactly - the 22.6m homes passed represent just 18% of total households in the US and Canada. At the current rate of deployment, it will take another nine years to get to 30% coverage (and even this is 'artificially' accelerated by government subsidy, which is unlikely to last).
A more likely reason for this decline in FTTH investment is that carriers are realising that is it very hard to make a return on such capex. A particular challenge for US carriers is the competition they face from cable operators, who have roughly 55% share of the broadband market and rising - something to keep in mind the next time you're told cable operators' HFC platforms are yesterday's technology which can never compete with FTTH.