Hayanaratna 5.15

Or 'adding the lagna degrees' also stands for adding the degrees of the 2nd house, the 3rd and so on. For example, the janma lagna (rising sign at birth) is Leo at twelve degrees. In the first year the muntha (the point that moves one sign each year) is right there. Then comes the 2nd house, at Virgo ten degrees. In the second year the muntha is in Virgo at ten degrees. Know it the same way everywhere.

Simple meaning: Adding the degrees: each year the muntha takes the degree of the house it reaches, like Leo 12 degrees, then the 2nd house at Virgo 10 degrees.