The time expression can be changed to
Transform(m.S_ToT, '@R 99:99'))
[Update]
And is not clear if S_Tot is numerical or string, you use it as both, but for the STR it seems your intention was to start with 1515 and not with "1515"
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Jorge L. Borges?
"Premature optimization is the root of all evil in programming."
Donald Knuth, repeating C. A. R. Hoare
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Jorge L. Borges
