The Chicago Fed National Activity Index (CFNAI) increased 0.34 in February following a revised 0.02 decline for January which was originally reported as a 0.05 decline.
The 3-month moving average strengthened to 0.25 from 0.07 previously and this was the highest level since December 2014.
Employment-related indicators contributed 0.21 to the overall index in February from 0.06 in January as the number of people reported as employed increased sharply.
Production-related indicators contributed 0.09 from 0.04 previously with support from a second successive 0.5% increase in manufacturing production.
The sales, orders and inventories component was also positive at 0.08 from -0.01 in January, but the personal consumption and housing category held in negative territory at -0.03 from -0.11 previously.
Any strengthening in the index to above 0.70 following a prolonged period of economic expansion suggests that a period of sustained increasing inflation has begun, but the index held comfortably below this level which suggests only a small increase in inflation is likely.
Overall, the indicator was pushed higher primarily by the impact of a sharp increase of 444,000 in the number of employed people in the February household employment report released as part of the non-farm payrolls data. This increase followed a reported decline the previous month and the index jump in December also reflected a sharp increase in the number of people reported as employed.
Without this component, the index would have registered only a small monthly improvement and the data overall suggests moderate growth in the economy with underlying consumer spending relatively subdued.