Correlating of the human age with the age of the rat* The age of  the  at the endof the phase Human age at the end of the phase
Entire life span 13.2 rat days =1 human year    
Weaning (nursing)period 42.4 rat days=1 human year 3 weeks
Day 21 (P21)
6 months
(180 days)
Pre-pubertalperiod 3.3 rat days=1 human year Approximately 6 weeks  Day 37 (P37) 11.5 years
(4198 days)
Adolescentperiod 10.5 rat days=1 human year Approximately
7-8 months (Day 210)
20 years
(7300 days)
Adulthood (Reproductive senescence) 11.8 rat days=1 human year 15- 20 months 
(600 days)
51 years
(18615 days)
Aged-phase(Post senescence) 17.1 rat days=1 human year Female rats live an average of 485 days after senescence Female humans live an average of 10,585 days after senescence
P= postnatal
Table 1: Correlating of the human age with the age of the rat.