Regular expression to extract a year from anywhere within a free text string

I need to write a regex that will match the 1st year from a line of free text, anywhere within the string.

The year will be 4 digits and will begin 20 or 21 (eg 2030 or 2199)

It should NOT match longer numbers like 20304050

here is some js code I have written with the output below, as you can see each regex works for some cases but none for all.

NB – the final version of this wont be JS, so I don’t want solutions that require additional code, just a pure regular expression, although I could live with the result with the extra full stop and truncate the results to 4 chars. Thanks

const values = [
  '2025',
  '2150 is the year to match',
  'the year is 2030 see ref 2099662',
  'Should match the year here YEAR_2140 even though it has non numric chars preceeding it',
  'Should match the year at the end of a string like this - 2140',
  'ref 2099662 the year is 2140. And there is another sentence',
  'ref 2099662 the end of the string is the year 2140',
  'There is no year here 2055667'
]
console.log('   regx1', 'regx2,', 'regx3,', 'input string')

values.forEach((value, index) => {
  value = value.trim()
  const regex1 = /2[01]{1}[0-9]{2}/
  const regex2 = /2[01]{1}[0-9]{2}[^0-9]{1}/
  const regex3 = /2[01]{1}[0-9]{2}[^0-9]{1}/

  const year1 = (value.match(regex1) || [])[0] || '     '
  const year2 = (value.match(regex2) || [])[0] || '     '
  const year3 = (value.match(regex3) || [])[0] || '     '

  console.log(`${index + 1}) ${year1}, ${year2}, ${year3}, "${value}",`)
})

This code outputs:

   regx1 regx2, regx3, input string
1) 2025,      ,      , "2025",
2) 2150, 2150 , 2150 , "2150 is the year to match",
3) 2030, 2030 , 2030 , "the year is 2030 see ref 2099662",
4) 2140, 2140 , 2140 , "Should match the year here YEAR_2140 even though it has non numric chars preceeding it",
5) 2140,      ,      , "Should match the year at the end of a string like this - 2140",
6) 2099, 2140., 2140., "ref 2099662 the year is 2140. And there is another sentence",
7) 2099,      ,      , "ref 2099662 the end of the string is the year 2140",
8) 2055,      ,      , "There is no year here 2055667",

>Solution :

(?:\b|\W)?(?<year>2(?:0|1)\d\d)\b

This pattern works for me:

const values = [
  '2025',
  '2150 is the year to match',
  'the year is 2030 see ref 2099662',
  'Should match the year here YEAR_2140 even though it has non numric chars preceeding it',
  'Should match the year at the end of a string like this - 2140',
  'ref 2099662 the year is 2140. And there is another sentence',
  'ref 2099662 the end of the string is the year 2140',
  'There is no year here 2055667'
];

const reg = /(?:\b|\W)?(?<year>2[01]\d\d)\b/g;

for (const v of values) {

  //const matches = reg.exec( v );
  const matches = Array.from( v.matchAll( reg ) );
  
  const matchJson = JSON.stringify( matches );
  addRow( v, matchJson );
}

function addRow( x, y ) {
  const tbody = document.getElementById('rows');
  const tr    = tbody.insertRow(-1);

  const tdInput = tr.insertCell();
  const tdMatch = tr.insertCell();

  tdInput.textContent = x;
  tdMatch.textContent = y;
}

table {
  border: 1px outset #ccc;
}

th,
td {
  border: 1px inset #ccc;
  padding: 0.5em;
}

<table>
  <thead>
    <tr>
      <th>Input string</th>
      <th>Match</th>
    </tr>
  </thead>
  <tbody id="rows">
  </tbody>
</table>