Yield on UCSD pension

As I was preparing for filing taxes, I paid some attention to my UCSD pension balance. When I quit UCSD last year, I left the pension there instead of taking out. It occurred to me to evaluate the yield on pension, so I made some calculations.

UCSD says my current pension balance is $170,599, and that if I start taking monthly payments at age 65, I would get $4,251 per month. I am currently 45 years old, and the life expectancy of a 45-year-old Japanese male is 37.28 years (see here). So I wrote the following Matlab code to calculate the yield.

C = 4251.04; % monthly payment
P = 170599.34; % present value
age = 45; % current age
expect = 37.28; % life expectancy
age_retire = 65; % age to retire
t = age_retire - age:1/12:100;
t = t(t<age + expect);

func = @(y)(C*sum(exp(-y*t))-P);
y = fzero(func,0);
y_percent = 100*y

The answer is 7.13%. Given that the U.S. stock market index has historically produced about 6.5% real return, this is a very good deal. But I need to pray for the solvency of the state of California.