You have forgotten that SBD has a high inflation as long as the price is above $1. Currently the inflation rate is 9% per week or 500% per year. This regulation mechanism results in a SBD price of $1 in the mid to long term.
This chart you'll also find in my weekly steemit statistics:
https://steemit.com/steem/@sevenseals/steem-statistic-charts-week-05-new-activity-chart-and-country-statistic-added