PMT not calculated same as Excel (yes I know it's OpenOffice)

[keslavi]

hey, I know this is an OpenOffice port, but I noticed that the implementation doesn't return the same PMT as Excel.

(Excel Example)
rate | time | principle | pmt |  
0.1 | 12 | 2000 | ($293.53) | =PMT(A2,B2,C2)

exports.PMT = function(rate, periods, present, future, type) {
      //formula:
      //PMT = PV x IR / (1 - (1 + IR) -NP)
      //converted to js:
      //PMT = (PV * IR) / (1 - Math.pow(1 + IR, -NP))
      //(ir,np,pv) =>{//(rate, time, principle)
  let pay = (present * rate) / (1 - Math.pow(1 + rate, -periods));
  return -pay;
  //your implementation goes on for additional  work but this was all I needed for mine

I'm comparing the values to an Excel sheet calculating PMT from $100-$5000 for a time period of 1-18 months and the above PMT lines up with Excel through the whole sheet.

Also, though this isn't technically an Excel function, I also use .toMoney to format like excel:

// eslint-disable-next-line
Number.prototype.toMoney = function(decimals, decimal_sep, thousands_sep)
{
     var n = this,
     c = isNaN(decimals) ? 2 : Math.abs(decimals),
     d = decimal_sep || '.',
     t = (typeof thousands_sep === 'undefined') ? ',' : thousands_sep,
     sign = (n < 0) ? '-' : '',
     // eslint-disable-next-line
     i = parseInt(n = Math.abs(n).toFixed(c)) + '',
     // eslint-disable-next-line
     j = ((j = i.length) > 3) ? j % 3 : 0;
     return sign + (j ? i.substr(0, j) + t : '') + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : '');
}