You can't because you have management fees reducing the BTC / share every year. Rather just make it a random number.

0.12% per year would mean 1% diff every 8 years. SPY has been able to keep it's price within a few % of 1/10 of SPX for +20 years and they even have the handling of dividends to manage for the difference. Every 10 years you can do a small stock split to rebalance if needed.