The Chicago Federal Reserve said on Tuesday that U. S. economic growth in April reached the highest level since December 2006.

The federal bank's monthly National Activity Index rose from 0.13 in March to 0.29 in April, which put national economic growth above the historic average for the third time in four months.

It was further reported that the National Activity Index sets the historic average at zero, which means the value of zero is a rolling average, but one that moves minimally from month-to-month.

Zero indicates the economy is growing at its average historic pace, while numbers above or below zero indicate growth is faster or slower than average.

The report further noted that the index is compiled from 85 economic indicators reflecting production and income, employment, personal consumption and housing, and sales, orders and inventories. (With Inputs from Agencies)