Your weight falls because the pool is growing. If you have 1 share and there are only 100 shares in the pool, you would receive 1% of the total weekly voting weight, or 70% total weekly voting weight. If you post once per day, that is 10% upvote on each post.
Now imagine the pool doubles to 200 shares. Your one share is now only 0.50%, or 5% upvote on each post, but the SP in the pool also doubles. So as your upvote weight drops, the upvote value would hold constant if the STEEM/SBD prices held constant.
The only reason your upvote value is dropping along with your weight dropping is because of the slide in STEEM/SBD prices.
i had not thought about that thanks a lot i thought there was a 100 share cap tbh hence more sbi's being created.
100 share cap per member in each pool, and 500 members per pool.
thanks 500 member per pool didn't know that =]
You're welcome.