Current 100Mbps/4U Pricing

I've been happily hosted in Equinix Ashburn for over a year now, so I haven't been looking into price changes over the past months. However, my colo provider suddenly decided to raise prices by 20% on me, saying that space and bandwidth has become scarce over the past year and their own cost went up by 75%. So they are asking me to lock the new hiked price by signing a new contract, otherwise I won't be able to get such offer from them or any other provider in that location.

Before signing anything, I'm trying to get a feel of the current prices. I see a lot of ads in here for same bw and space, but I'm sure there are variations in the level of service they provide, depending on the colo company, location, bw providers, package type, etc... So, just as crude estimate, can you please tell in general whether prices/costs has went up or down or stayed the same since last year, and by how much?

And if someone has experience with Equinix/Ashburn, what would be a reasonable price for a dedicated 100Mbps/4U colocation with a quality bandwidth provider?