I’ve started 3 times, and every time, regardless of how I play, my credit rating gets downgraded, repeatedly. On the last time I tried, I ran surplus budgets for the first 6 turns in a row, and then at the start of turn 7 my credit got downgraded. Is the game meant to do that? It doesn’t even make sense.
Your credit rating is determined by your debt/GDP ratio. If you look at the financial charts, it’s in the top right corner.
If you’re running a surplus, your debt is obviously decreasing. However (and particularly if you’ve introduced high taxes with a negative GDP effect) your GDP may well be dropping faster than your debt. Therefore, although your total debt is lower, your debt/GDP ratio is worse, and your credit rating gets downgraded.
It’s ok to run a minor budget deficit, provided it doesn’t run away from your GDP. Try focusing on boosting your GDP as a priority; as long as you keep a handle on your debt, you should find you’re doing better in the long run.
In the short-term, most scenarios start with the budget fairly unbalanced; this is probably part of the reason the opposition got voted out and you are now President! Don’t worry too much about dropping a few notches early on; you’ll make it back.
That did the trick, thanks. Now I just need to deal with the fact that I keep getting assassinated by religious nutjobs.
To lessen your chance of being assassinated you should “anger” the focus group slowly. By doing it too fast the % of that group could be pretty high and thus get you assassinated,but if you drop their membership values to 10%- I find it pretty hard to get assassinated (a well funded intelligence services helps too).
On my latest play though, I did exactly what you said Ulq, and it worked. I slowly did things to erode them, and the presence of religion in my country eventually died out entirely, (woo hoo!) I was then free to teach evolution in schools and develop stem cell research all I wanted without fear of assassination from those cold heads.
I find that effect to be a little ecessive as well. I had thought that it was a timed effect as well, because it happened on the same turn after many plays. … perhaps it is triggered by a timed “market meldown” instead.
Playing as the US, i noted the interest rate shout up to 7% that is way out of wack for t-bills, and the USA’s credit was down to a C, which is absurd, but i am not expecting IMF level accuracy for the simulation. It might be better to change the label on this effect to the “bond market reaction” since that changes a lot more frequently than sovereign credit ratings.
Overall i find the economic gyrations to be pretty extreme, its easy to get hit with a market meltdown on the eve of the election - in which event you are simply toast. 
Maybe if the economic gyrations were tamed the credit upgrades / downgrades are appropriate, it is just the economic affects which are extreme.