add salary to tldr stock options

(function createSalary() {
    var outcome = document.querySelector('.outcome');
    var el = document.querySelector('.salary-guess');
    if (el) {
        outcome.removeChild(el);
    }
    var div = document.createElement('div');
    div.setAttribute('class', 'salary-guess');
    div.innerHTML = "<div class='salary-guess'><input class='irr' type='text' placeholder='IRR %' value='7'></input><div class='calculated-profit salary'></div><div class='steps'></div></div>";
    outcome.appendChild(div);

    function newtonsMethod(f, df, x0) {
        console.log("x : " + x0);
        console.log("f : " + f(x0));
        console.log("df: " + df(x0));
        return x0 - f(x0) / df(x0);
    }
    function solveNpv(total, years, irr) {
        if (total <= 0 || years <= 0) {
            return 0;
        }
        function computeGrowth(salary){
            var s = 0;
            for (var y = 0; y < years; y++) {
                s = s*(1 + irr/100) + salary;
            }
            return s - total;
        }
        function dComputeGrowth_dSalary(salary) {
            return (computeGrowth(salary*1.01) - computeGrowth(salary)) / (salary * 1.01 - salary);
        }
        var steps = 0;
        var error = 11;
        var guess = 100;
        while (steps < 100 && Math.abs(error) > 10) {
            guess = newtonsMethod(
                computeGrowth,
                dComputeGrowth_dSalary,
                guess
            );
            steps = steps + 1;
            error = computeGrowth(guess);
            console.log(error);
        }
        document.querySelector('.steps').innerText = steps + ' steps to solve';
        document.querySelector('.salary').innerText = '$' + guess.toFixed(0) + ' /year (not adj)';
    }
    document.querySelector('input.exit-value').addEventListener('change', recompute);
    document.querySelector('input.irr').addEventListener('change', recompute);
    function recompute() {
        var years = parseInt(document.querySelector('.calculated.years').innerText);
        console.log('years ' + years);
        var payout = parseInt(document.querySelector('.calculated.profit').innerText.replace(/\$|,/g,''));
        console.log('payout ' + payout);
        var irr  = parseInt(document.querySelector('input.irr').value);
        solveNpv(payout, years, irr);
    }
})();