No. It was for last 3 years, but this year it's a mixed bag.
What happened is that everyone used to be the same, no matter when they purchased. And prices increased noticeably every year. Especially in the south and Light Grey, because to be honest, they had priced them too low compared to the other seats.
But when things went badly in 2011 (year 5) when they tried to hike the prices too high, (and include too many games). So they held 2011 pricing in 2012. But after another dreadful season, they came up with this year 1 pricing thing for 2013, but sold new tickets at closer to year 3 prices. Then after another dreadful year in 2014 they froze everyone at what they paid (2012 or 2013 prices) but sold new tickets close to year 5 pricing, with the whole Defoe/Bradley thing. Then in 2015, after yet another bad season, they froze again, sold a lot of new seasons at 2014 prices, and then switched late in the day to even higher prices than every before. Putting current seat holders at 4 different pricing levels, that vary drastically, based on when they first purchased.
Now in 2015, they are moving up the Year 1 pricing, but only moderately, except in the under-priced light-grey (but not the under-priced yellow). Hard to see exactly what they are doing everywhere, though some with 2014 pricing have been frozen.
If you look at the price per game, I tried to summarize as best I know, on Twitter a couple of weeks ago, over the years.
(price per game = divide total by the 19 games in recent years. In earlier years, premium (MLS Cup, friendlies) games were double. In 2007, MLSE assumed 20 games).
There appears to be some even weirder stuff going on this year, with different reported prices by Year 1 holders in Medium Grey in the east stands than the west stands. We'll be using PriceLine to pick our price at this rate ...