function(current_time, start_value, change, total_time) {
var ts=(current_time/=total_time)*current_time;
var tc=ts*current_time;
return start_value+change*(-1.55*tc*ts + 7.5*ts*ts + -12.3*tc + 7.3*ts + 0.05*current_time);
}
let arr = Array.from( tags );