premise: The 198th Infantry Brigade, was first formed as part of the United States Army Reserve's 99th Division. It was active from 1967 through 1971 and has been active since 2007 as an Infantry Training Brigade as part of the US Army Infantry School at Fort Benning, Georgia.
hypothesis: the 198th brigade ended its active status in 1971 
reason: it states it was active until 1971 and then later became active again in 2007