It doesn't seem particularly high, but generally people fall off over time. However, I wouldn't actually recommend this tactic as a way of gaining followers. 1

It doesn't seem particularly high, but generally people fall off over time. However, I wouldn't actually recommend this tactic as a way of gaining followers. 1) Following too many people erodes the value of your Twitter stream, its better to be invested in the people you follow. You'll get a lot more out of the experience. 2) Your followers won't actually be as engaged as they would have been if they had found you though more organic growth. 3) I think people tend to judge accounts that are following way more people than follow them...but maybe that's just my own bias.