Estimate field allows to identify original, current, elapsed and remain time required to resolve the record.
"Original" time estimate entered once and can't be changed.
If it takes longer or shorten to resolve the record user can correct "Current" time estimate. To specify how much time was spent to resolve this record "Elapsed" time should be used.
System will automaticaly calculate "Remain" time as diffirence between "Current" and "Elapsed" time.
"Original" and "Current" inputs are needed to evaluate how close is planning to reality.
