minimum / maximum / average climb / average descent in%

I have a Garmin Edge 530 and I find it cannot record the minimum / maximum / average climb / average descent in%.
Even on connect IQ in applications or data fields is not a similar application (except hGradeMax), which, however, measured by GPS not according to the built-in barometer and therefore is almost unusable. According to hGradeMax, data cannot be accessed from the built-in barometer.
Could you incorporate this into your system in another Edge 530 software update? Average, minimum / maximum percentages of ascent / descent can even cheap tachometers with barometric altitude measurement why Garmin can't do this?