User`s guide

Remarks
The calibration counts increment up to a maximum of over four billion
(2
32
- 1) after which they roll over to "0". Since the value increments by
one for each calibration point, a complete calibration may increase the
value by many counts. However, it is unlikely that the count will ever roll
over due to the high maximum.
The calibration count is incremented by the CALibration? command. You
can read the calibration count whether the instrument is secured or
unsecured.
The calibration count is stored in non-volatile memory, and does not
change when power has been off, after a Factory Reset (*RST command),
or after an Instrument Preset (SYSTem:PRESet command).