Original sentence: Beginning in 1985, United started the process of migrating its CLE hub capacity to Washington Dulles International Airport; this process was completed in 1987.Continental and Hopkins both made substantial operational and capital investments in support of CLE; this included the construction of Concourse D in 1999 to provide accommodations for Continental Express flights.Continental increased its hub capacity at Hopkins, becoming the airport's largest tenant and eventually accounting for upwards of 60 percent of passenger traffic.From the postwar era until the mid-1980s, United Airlines maintained its eastern-most domestic hub at CLE.The same year, Continental Airlines, which was then a separate carrier and lacked a Midwest hub, quickly moved into fill the void left by United.This gave the then Continental hubs in five markets: Houston, Denver (subsequently dehubbed), Newark (per its acquisition of People Express in 1987), Guam and Cleveland
Edited sentence: At the time, Continental lacked a hub in the Midwest but maintained hubs in Houston, Denver (later abandoned as a Continental hub, but now a United hub), Guam, and Newark (the latter as a result of Continental's 1987 acquisition of People Express Airlines).Continental and Hopkins both made substantial investments in support of Continental's presence at the airport, including the 1999 construction of Concourse D, primarily to accommodate Continental Express flights.Continental increased its presence at Hopkins and became the airport's largest tenant, eventually handling as much as 60% of passenger traffic.For many years in the postwar era, United Airlines had a strong presence in Cleveland.The former Continental Airlines (now merged with United Airlines as part of United Continental Holdings) began its efforts to establish hub in Cleveland in the late 1980s when United Airlines, then a separate carrier, dramatically reduced its operations in Cleveland and relocated most of its flights to Washington Dulles International Airport