In Janam Kundli there are some points or zones which are very sensitive. They are trouble causing points. One of such point is 64th Navamsha. Classics states that what
ever is the navamsha of the lagna, exactly the same navamsha of the 8th sign from the lagan is 64th navamsha. As a thumb rule the 4th sign from the navamsha lagna is the 64th navamsha. It is believe that the rule of 64th navamsha gives more better results from moon rather than lagna. So to understand the above concept easily follow the simple steps
1) Locate the position of Moon in Navamsha chart.
2) Count the 4th sign from that
3) Check the dasha of that lord.
The dasha of lord of 64th navamsha generally brings ill health. One thing is clear that 8th house from lagna holds important key because the 64th navamsha falls here.
Variation-2 Now in an interesting variation of the above rule one can fetch important results if the 64th navamsha of all planets is taken into account. For example when a planets transit in the 64th navamsha from the dasha/antardasha nath then the house which is own by the transiting planet will suffer.
Variation-3 In Lagna Kundli check the planets which are falling in 64th navamsha of any planet. Now when the dasha of the planet operates then the planets falling in 64th navamsha from it will suffer.
I have tried to give the parameter which I use often.