Handy Google spreadsheet function to download and parse NAVs uploaded regularly by the AMFI.

GetMF.gs

// This code is in Public domain.

MF_SCHEME_NAME = 3;
MF_NAV = 4;
MF_DATE = 5;
CACHE_NAME = '_mfcache';

function initNAV() {
  var response = UrlFetchApp.fetch("http://portal.amfiindia.com/spages/NAVAll.txt");
  var txt = response.getContentText();
  data = Utilities.parseCsv(txt, ";");
  var newdata = [];

  var earnings = SpreadsheetApp.openById(/* Put your Google spreadsheet ID here */);
  mfcache = earnings.getSheetByName(CACHE_NAME);
  
  if (mfcache == null) {
    mfcache = earnings.insertSheet(CACHE_NAME);
  }
  
  // I have designated a column as a source for MF codes.
  my_mfs = earnings.getSheetByName('My MF Sheet').getSheetValues(2,2,-1,1);
  Logger.log(my_mfs);

  // Filter out unnecessary gunk.  
  for (i = 0, j = 0; i < data.length; i++)
    if (data[i][MF_NAV] != '')
      for (k = 0; k < my_mfs.length;k++)
        if (my_mfs[k][0] == data[i][0] && (j == 0 || newdata[j-1][0] != data[i][0]))
          newdata[j++] = [data[i][0], data[i][MF_SCHEME_NAME], data[i][MF_NAV], data[i][MF_DATE]];

  data = newdata;
  Logger.log(data);

  mfcache.clear();
  // Delete all columns.
  if (mfcache.getMaxColumns() > 4)
    mfcache.deleteColumns(1,mfcache.getMaxColumns() - 4);
  mfcache.appendRow(['Last Updated', new Date()])
  for (r = 0; r < data.length; r++) {
    mfcache.appendRow(data[r]);
  }

  SpreadsheetApp.flush();
}