Jekyll page rating calculator with meta from Front Mater area

I am editing include/span with the following code pretend to be as "Jekyll page rating calculator with meta from Front Mater area" but it seems like some syntax missing an extra heading/lines to let calculation to display in left bottom round quotes. Now there is no value

See the sampl page

<span class="indexmod">
{% assign number_of_words = content | strip_html | number_of_words %}
{% assign social = page.facebook | plus: page.instagram %}

{% comment %}Two lines for readability, but can be chained on one line{% 
endcomment %}
{% assign Indexmod = social | times: page.age | divided_by: 1000000.0 %}
{% assign Indexmod = Indexmod | times: number_of_words | divided_by: 100 
 %}
{% endunless %}
 </span>

There are two reasons why this doesn't work:

• The {% endunless %} in this include is missing a matching unless clause. Either add one or remove the endunless line.
• The value of Indexmod is not printed. You can do that by adding {{ Indexmod }} after your calculations are done.