generate questions: One wave of the population boom ended abruptly in the mid-1980s, as oil prices fell precipitously. The space industry also suffered in 1986 after the Space Shuttle Challenger disintegrated shortly after launch. There was a cutback in some activities for a period. In the late 1980s, the city's economy suffered from the nationwide recession. After the early 1990s recession, Houston made efforts to diversify its economy by focusing on aerospace and health care/biotechnology, and reduced its dependence on the petroleum industry. Since the increase of oil prices in the 2000s, the petroleum industry has again increased its share of the local economy.
In what year did the space shuttle Challenger explode after launch? {sep_token} Why did Houston's economy have problems in the late 1980's? {sep_token} In the 1990's, what is something Houston did to try to diversify it's economy? {sep_token} The petroleum industry has become a larger part of Houston's economy again for what reason? {sep_token} What caused population growth to decline  in the 1980s? {sep_token} When did Houston begin to regain its dependence on the oil industry? {sep_token} What did Houston focus on after the 1990s recession to improve its economy? {sep_token} When did Houston suffer an economic decline? {sep_token} Which shuttle disintegrated in 1986 to cause a decline in the space industry? {sep_token}