You have started with off-page activities just within four months, worrying about PR of your site? Don't get so curious about page rank of your site because Google Page Rank algorithm evaluates well-crawled and indexed back links, which is one of major factor for attaining Page Rank. PR is usually updated after 3-4 times in a year. Right now, you focus on building quality back links for your website which will result in increasing page rank of your website.
PR depends on various significant factors such as domain-authority, quality of back links, reputation of your site, inbound and outbound links, page authority, content value and more.
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Through this, hope you will now have more clarity and understanding.