#s(tz
   (#s(span #s(*date 2006 10 1 0 0 0 -18000) -21600 0 2006 "CST")
    #s(span #s(*date 2006 4 30 0 0 0 -21600) -21600 3600 2006 "CDT")
    #s(span #s(*date 1991 9 7 0 0 0 -18000) -21600 0 1991 "CST")
    #s(span #s(*date 1991 3 23 0 0 0 -21600) -21600 3600 1991 "CDT")
    #s(span #s(*date 1983 9 22 0 0 0 -18000) -21600 0 1983 "CST")
    #s(span #s(*date 1983 5 21 0 0 0 -21600) -21600 3600 1983 "CDT")
    #s(span #s(*date 1974 2 24 0 0 0 -18000) -21600 0 1974 "CST")
    #s(span #s(*date 1973 11 25 0 0 0 -21600) -21600 3600 1973 "CDT")
    #s(span #s(*date 1918 10 5 0 0 0 -21724) -21600 0 1918 "LMT")
    #s(span -inf.0 -21724 0 -inf.0 "LMT"))
   #s(*zone-span -21600 () "C~aT")
   (#s(span #s(*date 1918 10 5 0 0 0 -21724) -21600 0 1918 "LMT")
    #s(span -inf.0 -21724 0 -inf.0 "LMT")))