1. A computer implemented method of extracting structural label and value pairwise data associated with a digital version of a document, the method comprising: a) performing a layout analysis of the digital version of the document to generate one or more layout structures associated with the document, each layout structure including a plurality of structural elements vertically or horizontally aligned where each structural element is defined as a typographical box including one or more lines of textual elements associated with the digital version of the document; b) processing the one or more lines of textual elements to identify and tag textual elements associated with label and value pairwise data; c) processing the one or more layout structures and associated tagged textual elements to generate one or more respective label:value sequences of tagged textual elements representative of a respective layout structure; and d) extracting label and value pairwise data from the one or more label:value sequences of tagged elements.