Read specific blocks txt php and extract values - php

Question

I'm doing social service, the idea is to automatize a process. I already capture other values using regex, like:
<?php function LeerEncabezado() {
$fh = fopen('RPREGFM_________007_001.txt', 'r') or die('lel'); $file =
str_replace(',', '',
file_get_contents("RPREGFM_________007_001.txt")); $f =
fopen("RPREGFM_________007_001.txt", "w"); fwrite($f, $file);
fclose($f); while (!feof($fh)) {
$line = fgets($fh);
//Intermedio
if (preg_match('/INTERMEDIO (?<cfintermedio>[\w]+.+)/i', $line, $r1)) {
$CFINTERMEDIO = substr($r1['cfintermedio'], 13, 8);
echo "C.F. Intermedio: $CFINTERMEDIO";
echo '<br/>';
}
//Base
if (preg_match('/BASE (?<cfbase>[\w]+.+)/i', $line, $r2)) {
$CFBASE = substr($r2['cfbase'], 13, 8);
echo "C.F. Base: $CFBASE";
echo '<br/>';
}
//kVArh
if (preg_match('/F.P. (?<fp>[\d]+.+)/i', $line, $r3)) {
$anioi = substr($r3['fp'], 0, 5);
echo "kVArh: $anioi";
echo '<br/>';
echo "--------------------------------------</br>";
}
//Base promedio
if (preg_match('/201912 (?<fp>[\d]+.+)/i', $line, $r3)) {
$anioi = substr($r3['fp'], 8, 5); // echo "kVArh: $anioi";
echo '<br/>';
echo "--------------------------------------</br>";
}
} } LeerEncabezado();
fclose($fh);
And it's working until his point, I got to take 3 values from that text block, the last number in INTERM column, BASE and % M$. In this receipt, it would be 1,5,99.98%. I've used strg_replace before for, I guess ill use it for the %. So I can compare those variables with other in the same receipt.
How can I extract those value taking in mind that the 201912 it's going to change taking in consideration the year and the number of rows in MES might change? Pretty much used the blank space and the read the previous line which it's going to be the one where the 3 values are in?
MES TOTAL PUNTA INTERM BASE TOT PTA INT BAS % M$
201901 9 1 7 744 122 622 99.96
201902 8 1 6 672 107 565 99.97
201903 9 1 7 744 115 629 99.97
201904 9 2 7 719 122 597 99.97
201905 10 1 8 744 88 656 99.98
201906 10 1 8 720 80 640 99.97
201907 12 2 10 744 92 652 98.89
201908 13 2 11 744 88 656 97.74
201909 11 1 9 720 80 640 97.05
201910t 1 7 624 76 548 97.56
201910 10 1 120 20 100 98.80
201911 8 1 6 721 115 606 99.20
201912 7 1 5 744 117 627 99.98