Such a request shall be made within one year as of the marriage registration date.

"On the one hand, the U.S. has come to a certain saturation of energy use, but there have also been lots of efforts, especially since 2005, to use energy more efficiently," he said.

Indeed, India's TFP growth in farming has fallen since 1993, dragging down overall TFP growth because agriculture still employs a large share of the population.