Now, my prior was that present tense should generally be used to present research results. Some examples:
- Overall, value traded of members ranges from 14% to 20% in our sample
- Some members account for up to 34% of total trading
- For members of group A, total trading is estimated at 25%
However, both 1. and 3. would sound better in past tense, I think. Is there a specific rule that I can follow with regard to tense, both in general as with regard to my examples?