C
C   Subroutine SORT sorts array WORD using
C   a simple exchange sort (sinking sort).  The array IS put in
C   ascending order based on the DATE field of WORD which consists of 
C   five characters starting at position 29 of each word.
C   LEN is the number of entries in the array.
C
        SUBROUTINE SORT (WORD, LEN)
        CHARACTER*35 WORD(1000), TWORD
        INTEGER LEN
        INTEGER J, K
        LOGICAL EXCH
        J = 1
13      EXCH = .FALSE.
C
C   Loop to do one pass over the array, exchanging adjacent entries
C   as necessary.
C
        DO 11 K = 1, LEN - J
            IF (WORD(K)(29:33) .GT. WORD(K+1)(29:33)) THEN
                TWORD = WORD(K)
                WORD(K) = WORD(K+1)
                WORD(K+1) = TWORD
                EXCH = .TRUE.
            ENDIF
11      CONTINUE
        J = J + 1
C
C   Determine if another pass is needed
C
        IF (EXCH) GO TO 13
        RETURN
        END