Even if you keep your file in .xlsm format what mostly matters regarding speed is how calculations are performed, what level of complexity formulas have, when are macro triggered, and so on.
So for more accurate comments consider uploading a sample file (including manual examples of desired output), it'd be very useful for those who read this and might be able to help you. Thank you. Give a look at the second green sticky post at this forums main page for uploading guidelines.