Cedar Rapids-based HR Green Inc. has been named to The Zweig Letter Hot Firm List for the second year in a row. The company, which has an office in Johnston, is ranked No. 12 on this year’s list, advancing from a 17th-place ranking in 2011. The Zweig Letter 2012 Hot Firm List recognizes the 100 fastest-growing architecture, engineering, planning and environmental consulting firms in the United States and Canada. For 2012, firms were ranked according to their three-year growth rate in gross revenue.