Over the past year, builders and developers were busier than they’ve been in years. Lagging housing sales during the recession brought on a demand for rental apartments, eventually leading to a rebound in housing construction as well. Though construction is still historically low, it’s in the best shape it’s been since the crash. Nearly 10,000 units are being planned, showing a 99.5 percent increase. And these numbers are mostly representative of actual sales not just company inventory. Tony Madden, a regional economist at the Federal Reserve Bank of Minneapolis, predicts that the good news will carry into 2013.