Śrīmad-Bhāgavatam · Text 3.11.12
Who is speaking and story frame
अयने चाहनी प्राहुर्वत्सरो द्वादश स्मृत: ।
संवत्सरशतं नृणां
परमायुर्निरूपितम् ॥ १२ ॥
ayane cāhanī prāhur
vatsaro dvādaśa smṛtaḥ
saṁvatsara-śataṁ nṝṇāṁ
paramāyur nirūpitam
Two solar movements make one day and night of the demigods, and that combination of day and night is one complete calendar year for the human being. The human being has a duration of life of one hundred years.
Read this verse on Vedabase.ioThis verse has no purport; its meaning is explained by the verses around it.