[SQL] Db2 z/OS - SYSIBM.SYSTABLES.CARDF does not equal COUNT(*)

Why does this:

SELECT
CARDF AS "ROW_COUNT"
FROM SYSIBM.SYSTABLES TABLES
WHERE TYPE = 'T'
AND "OWNER" = 'MY_SCHEMA'
AND NAME = 'MY_TABLE'
;


have a different result than this:

SELECT COUNT(*) AS "ROW_COUNT"
FROM MY_SCHEMA.MY_TABLE
;




EDIT:

The left number in the screenshot belongs to the SYSIBM.SYSTABLES query. The right number to the COUNT query.

The table does not contain CLOBs or other BLOBs but large VARCHAR columns.

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