>Certainly not the fastest, but (I believe) one of the shortest:
>

INT(m.lnNumber*10^m.lnDecimalPlaces)/10^m.lnDecimalPlaces

>Also, it won't give you the nearest lower number, but the nearest number closer to zero.

Hello and thank you

In the mean time I found it myself:

DesiredNumber = ROUND(GivenNumber - .5*10^-DecimalPlaces,DecimalPlaces)

Thanks, anyway.