Average maximum mobile  broadband download speeds registered their greatest ever quarterly gain in 1Q 2012, at least since Strategy Analytics began tracking them in 2009, according to the Boston-based market research firm’s latest Mobile Broadband Price Benchmarking Service.

Average  maximum mobile broadband download speeds now exceed 14 Megabytes per second (Mbps) and are forecast to approach 20 Mbps per second  by year-end, according to Strategy Analytics’ report. Data allowance capacity is also on the rise, with averages now exceeding 8 gigabytes per month. They’ll average more than 10 gigabytes per month by the end of the year, Strategy Analytics forecasts.

A wave of 4G and LTE mobile network rollouts and device introductions, along with carriers upgrading to 3.5G and versions of HSPA/HSPA+, is fueling the increases in both average mobile broadband download speeds and data allowances, Strategy Analytics’ analysts say.

“Since December there has been a 20 percent increase in the number of plans that advertise maximum download speeds in excess of 21 Mbps,” commented report author Pawel Kmiec. “These plans are followed by the Strategy Analytics Mobile Broadband Price Benchmarking service.”

North America continues to set the pace in terms of 4G LTE subscribers, according to recent data gathered by Informa Telecoms & Media for 4G Americas. More than 2/3 of the global LTE subscriber base– more than 10.5 million individuals– resided in North America as of the  end of Q1.