Final answer:
The question regarding FedEx Express's achievement in surpassing fuel economy improvements cannot be answered without specific data from the company's reports or releases.
Step-by-step explanation:
The question about FedEx Express's improvement in fuel economy doesn't provide specific progress figures for FedEx Express itself. The details given are related to general fuel economy statistics and policy, such as the 2009 announcement by President Barack Obama regarding national fuel economy and emissions policy, which required that the combined fleet fuel economy of an auto manufacturer of cars and light trucks average at least 35.5 mpg by 2016.
Without specific information on FedEx Express's achievements regarding fuel economy improvement, it is not possible to accurately determine the percentage by which they surpassed their goal ahead of schedule. To answer the question about FedEx Express's specific fuel economy improvements, it would be necessary to have data or a press release directly referencing their accomplishments.