Fix earnings record table for entries with earnings prior to 1966. #185

Add text to one of the FAQ entries calling out the limitations with
respect to:

 - Special Extra Earnings for Military Service #186
 - Windfall Elimination Provision #94

This does not actually resolve #186 or #94, it just calls them out as
sources of error in the text.

partials/frequent-questions.html

@@ -99,17 +99,43 @@ <h2>Additional Questions</h2>
     <ul>
       <li>
         Income tax withholding
-        [<a href="https://www.ssa.gov/planners/taxwithold.html">ssa.gov</a>]
+        [<a href="https://www.ssa.gov/planners/taxwithold.html"
+          target="_blank">ssa.gov</a>]
       </li>
       <li>
         Medicare (health insurance) Part B premium
         [<a
-          href="https://www.medicare.gov/your-medicare-costs/paying-parts-a-and-b/pay-parts-a-and-b-premiums.html">medicare.gov</a>].
+          href="https://www.medicare.gov/your-medicare-costs/paying-parts-a-and-b/pay-parts-a-and-b-premiums.html"
+          target="_blank">medicare.gov</a>].
       </li>
       <li>
         Garnishments (ex: back taxes, student loans, alimony, child support).
       </li>
     </ul>
+    <p>
+      There are also some smaller factors which this calculator does not
+      currently take into account fully, but may be added in the future. These
+      include:
+    </p>
+    <ul>
+      <li>
+        Special Extra Earnings for Military Service from 1957 - 2001 [<a
+          href="https://www.ssa.gov/benefits/retirement/planner/military.html"
+          target="_blank">ssa.gov</a>]. This can add as much as an additional
+        $1,200 per year on your earnings record. For most, the effect
+        is only a few additional dollars per month in benefits, but in rare
+        cases this can be as high as hundreds of extra dollars.
+      </li>
+      <li>
+        Windfall Elimination Provision [<a
+          href="https://www.ssa.gov/pubs/EN-05-10045.pdf"
+          target="_blank">ssa.gov</a>]. This provision can reduce the monthly
+        benefit for those who earn a retirement or disability pension from an
+        employer who didn't withhold Social Security taxes (typically a
+        Government pension). The reduction can be up to half the value of the
+        pension. About 3% of Social Security beneficiaries are affected.
+      </li>
+    </ul>
   </section>
   <section class=frequent-questions>
     <input type=checkbox id=q5>

src/ssa-parse.mjs

@@ -13,6 +13,10 @@ var dollarStringToNumber = function(dollar_string) {
   // yet been filed. Record this as a -1 sentinel for now.
   if (dollar_string === 'NotYetRecorded')
     return -1;
+  if (dollar_string === 'MedicareBeganIn1966')
+    return 0;
+  if (dollar_string === '')
+    return 0;
   var number_string = dollar_string.replace(/[$,]/g, '');
   return Number(number_string);
 }
@@ -26,7 +30,11 @@ var parseSsaGovTable = function(lines) {
     var record = new EarningRecord();
     record.year = Number.parseInt(columns[0]);
     record.taxedEarnings = dollarStringToNumber(columns[1]);
-    record.taxedMedicareEarnings = dollarStringToNumber(columns[2]);
+    if (columns.length > 2) {
+      record.taxedMedicareEarnings = dollarStringToNumber(columns[2]);
+    } else {
+      record.taxedMedicareEarnings = 0;
+    }
     earningsRecords.push(record);
   }
   return earningsRecords;
@@ -96,6 +104,10 @@ var parsePaste = function(paste) {
   // Some columns will include the string "Not yet recorded" which breaks
   // columns on spaces in the string. We replace these with "NotYetRecorded".
   replacedStr = replacedStr.replace(/not yet recorded+/gi, "NotYetRecorded");
+  // Similarly, for records in 1965, the Medicare column will include the
+  // string "Medicare Began in 1966". We replace this with:
+  // "MedicareBeganIn1966".
+  replacedStr = replacedStr.replace(/medicare began in 1966+/gi, "MedicareBeganIn1966");
 
   // Split based on newlines.
   let lines = replacedStr.split("\n");