The following chart lists the calculation of the full-period duration of the 12000 year cycle containing the 4 minor and uneven periodic cycles is as follows:
Treta Yug 200 + 2000 + 200 = 2400
Dwapar Yug 300 + 3000 + 300 = 3600
Kali Yug 400 + 4000 + 400 = 4800
Total Years = 12,000
From Vishnu Puran, Part IV, Chapter 24, Versus 109 and 113, we learn that
"on the day Bhagwan Krishna ascended to His Holy Abode,
at the age of 126 lunar years. In Vishnu Puran it is also stated that so long as Bhagwan Shri Krishna was touching this earth with His Lotus Feet, Kali Yug could not put it's foot on the earth."
Most Hindus today believe that Kali Yug is an evil age. The word "Kali" has a dual meaning... on one hand Kali depicts a beautiful bud and a fragrant rose. On the other hand in later stages of it's life cycle it depicts a flower which has died, decayed and dried up. The same is true of the life cycles of religion. In the beginning, religion is like a beautiful bud and a fragrant rose because whenever one of God's Prophets or Manifestations appear
on Earth... He most renews Religion, and a new era of Righteousness in the world of Humanity is born. Similarly, like the beautiful rose which eventually dies, decays and dries up... religion's regenerating force and life giving vitality is obscured.
Hence, there are clear-cut prophecies in the Hindu Scriptures about the bad events to
come and evil occurrence to happen in the end-times of Kali Yug.
This is the example provided to us by Shri Krishna's religion. Krishna originally did establish a beautifully budding civilization and a spiritualized nobility which
flourished like the opening of a "Kali" petal... of a fragrant rose. Krishna claims: "I am the flowery Spring Season" ("Aham Rutuna Kusumakarah")---Gita X.
So Kali originally was a budding age of goodness, which gradually and progressively declined until it finally died 5065 lunar years later... in 1844 A.D.
From these 5065 lunar years we deduct the 126 years of Shri Krishna's life on earth. This leaves us with 4939 lunar years of 355 days each (4939 x 355 = 1753345 days.) If we convert these 4939 lunar years into solar years of 365.25 days each we get 4800.3969 solar years. (4939 x 355 = 1753345 days divided by 365.25 days in a solar year= we get 4800.3969 solar years.
The year 4800.3969 of the Hindu calendar is the year 1844 A.D. of the Christian calendar. This prophecy says that Kali Yug will end in the year 1844 A.D. It also promises that by the end of Kali Yug age (or 1844 A.D.) there will appear a Manifestation of God Who will inaugurate a new "krityug" or a new "age of deeds".