Relative Happiness Index

The RHI represents a new means for quantitatively assessing the general state of mind of populations and comparing them. RHI came to my mind when I was thinking today about my problems (at least I call them problems ;-)). And I could recall problems that my friends/colleagues/acquaintances shared with me.. And immediately I felt good.. Why?? Is it because happiness is an abstract, personal, and relative notion?? I feel better when I get to know about other peoples' problems?? Why is it like that?? Life is a b**** at times...