Engaging leads within the first five minutes

We need to have a feature in Hubspot to measure Sales Response Time from when the lead is created and first contacted. Hubspot currently has Last Contact Date, however, the First Contact Date property is missing. It will be an excellent addition to Sales Management. 


All the courses from HubSpot says that the contacts must be contacted within the 5 first minutes. How that there is no way to check this? It goes against what the learning center says.