AT&T slows unlimited data speeds past 3GB, 5GB for unlimited LTE An AT&T logo is displayed on an AT&T truck in Park Ridge, Ill. Tim Boyle/Getty Images / July 26, 2006 By Nathan Olivarez-Giles March 1, 2012, 2:15 p.m. AT&T is, yet again, switching up how it slows down data speeds for its remaining unlimited data plan users. On Thursday, the carrier said it would slow uploads and downloads for 3G (HSPA+) users who consume more than 3 gigabytes of data in a month. If you're using a 4G LTE phone from AT&T and you have an unlimited data plan, then you'll see slower data speeds when you consume more than 5 gigabytes of data in a month. Back in June, AT&T implemented a policy of slowing its unlimited data users' speeds only when they fell into the top 5% of users in terms of consumption -- with the changes, that policy is being abandoned. Previously, AT&T didn't slow speeds for unlimited data users. If you have AT&T service and are on one of the company's tiered data plans, then the changes don't affect you. The changes follow AT&T pushing its tiered data plans to higher prices and higher data caps last month. The reason for the moves? AT&T said on its website this is all a response to "soaring mobile broadband usage and the limited availability of wireless spectrum." The Dallas-based telecommunications giant said its seen a 20,000% increase in data consumption by its users over the last five years, and has gone from 7 million smartphones on its network in 2006 to 39.4 million in 2011. In that five-year time span, AT&T says its spent more than $95 billion to build out its network, both wireless and wireline, and that it plans to spend another $20 billion in network upgrades this year. AT&T's new pricing: more data for more money AT&T closes $1.9-billion purchase of Qualcomm spectrum AT&T's 4G LTE enters 11 new markets, including Los Angeles