Jack Cutrone wrote:

It is apparent
that Excel is interpreting the entry as a time of day rather than a
duration.
How can I stop this?

It's a fundamental problem. Time is in continuum rather than a series
of discrete values. Excel lacks an interval data type. You should model
duration as the period between two DATETIME values i.e. use two columns
e.g. start_date and end_date respectively.

there are over 12,000 records in the
spreadsheet so PLEASE don't suggest anything that requires reentering
all the
data :)

Oh. Forget I mentioned anything ;-)

Jamie.

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