The Purchasing Managers Index for Britain\'s construction sector rose significantly in March, the Chartered Institute of Purchasing & Supply said Tuesday. The PMI, which indicates business growth with numbers above 50, rose from 54.2 to 56.7, a 12-month high that also represents the sharpest month-to-month increase in 21 months, said the report, which is co-produced by Markit Economics. The overall index has now indicated growth in construction in Britain for each month since January 2011. The report for March said growth was reported in the three major construction categories of housing, commercial construction and civil engineering. Commercial construction posted the strongest numbers for the month, but civil engineering rose at the fastest rate since March 2011. Residential construction also showed growth, but \"only a slight increase ... was indicated,\" Markit said.