It is a delay calculated by Skyflow as per submitted flight plan data by using a complex algorithm  and the delay presented on  C-ATFM Portal is as follows:

 o ALDT – ELDT or

 o CLDT – ELDT (if ALDT is not available) or

 o ATOT – ETOT (if ALDT and CLDT are not available) or

 o CTOT – ETOT (if ALDT, CLDT and ATOT are not available) or

 o Zero, (if ALDT, CLDT, ATOT and CTOT are not available)

Considering the complex algorithm used, it is always advisable to crosscheck delay to a flight with concerned Airline Operator