<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NAME> JANUS MID CAP
<NUMBER> 9
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
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<INVESTMENTS-AT-VALUE> 2,473,292,017
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<SHARES-COMMON-PRIOR> 52,874,145
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<APPREC-INCREASE-CURRENT> (375,778,896)
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</TABLE>