<ARTICLE>                     5

<LEGEND>
Exhibit 27
                             Financial Data Schedule
                    Mylan Laboratories Inc. and Subsidiaries
                           Article 5 of Regulation S-X

The  schedule  contains  summary  financial   information   extracted  from  the
Consolidated Balance Sheet at September 30, 1999, and the Consolidated Statement
of Earnings for the six months ended September 30, 1999, and is qualified in its
entirety by reference to such financial statements.
</LEGEND>

<CIK>                         0000069499
<NAME>                        none


                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>               MAR-31-2000

<PERIOD-END>                    SEP-30-1999

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