Total Return of Alpha Picks

Today I made a virtual portfolio of all Alpha Picks. I used simplywall.st, a very good finance site. All shares have been wighted with about 1000 USD with the historical prices  The Total Return is 15,24% ( 13.87% Capital Gain, 1.57% Dividend Income and -0.19% Capital Gain. This is quite equal to S&P`s 15.84 and not 30.67%. The last is the number I can read  named Alphas Performance. Would you please explain me this?