Total Order Amount (calculated field TotalAmount) is Rounded Twice

Total order amount (calculated field) is rounded twice:

• in calculated field declaration (MySQL ROUND(<expr>, 2) function)
• in virtual field associated with given calculated field (via formatter)
  When site uses multiple currencies, then all prices are stored in database
  in primary currency. All currency conversions work, except for TotalAmount
  calculated field, because of double round it operates with M.NN number
  instead of M.NNNN and looses some cents during conversions of course.
  For example:
• Site primary currency is LVL
• Current currency on Front-End is EEK, which has 0.0449 conversion rate
  related to LVL
• Product price is: 26.9827 LVL
• Shipping price is: 3.0061 LVL
  Field TotalAmount shows 669.93, but it should show 667.90 instead.