Has anyone else noticed a dramatic drop in Facebook post impressions?

[UnderRugSwept]

One of the clients I manage has over 5,000 Facebook fans. Whenever I'd make a post, it usually would get ~700-1,000 impressions.

About two weeks ago I did my first promoted post. Ever since then, all the regular posts I've done have only gotten ~100 impressions . . . out of 5,325!

I'm wondering if Facebook, once learning that you are willing to pay for promoted posts, secretly lowers your impression count so that you will pay for promoted posts more often, or if the timing of my promoted post was just a coincidence, and everyone started to see a decrease about two weeks ago.

Does anyone know what's going on?

[firstconversion]

Facebook changed their algo a little while back. have a google

http://blog.hubspot.com/blog/tabid/6307/bid/33410/Facebook-Radically-Changes-Reach-Metric-How-You-Were-Affected.aspx

[UnderRugSwept]

Thanks for the link, but this happened radically and exactly two weeks ago.

[DavidKonigsberg]

I have heard others complain of drops after starting ads to promote posts but i have never seen any data to support it.