You can actually do this without clusters in one of two ways:
1) LV stores time as the number of seconds that have passed since 1/1/1904 00:00:00, so you can store this number. To do this, use the Get Date\Time VI from the Time&Dialog palette, and convert the timestamp to a DBL (using To DBL from the Numeric>>Conversion palette). This isn't readable because the number is currently 3.something * 10e9 but LV can turn it back into time. I suggest using this method because you can easily manipulate this time format in LabVIEW (compare, add, subtract and so on).
2) The other way would be to create a number to represent your data (like 10022004). This has several problems and I think using clusters is preferable.
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