We study how human capital diversification, in the form of double majoring, affects the response of earnings to labor market shocks. Double majors experience substantial protection against earnings shocks, of 56%. This finding holds across different model specifications and data sets....

Purpose - As of December 2022, there were 119,000 gas stations, 10,800 gas stations and 4,488,000 charging piles nationwide, while the number of vehicles reached 312 million, including 11.49 million new energy vehicles. The imbalance between transportation energy supply and energy replenishment...