Edmund P. Learned, C. Roland Christensen, and William D. Guth invented the Personal SWOT Analysis in the 1960s. Heinz Weihrich expanded on the concept in 1982, creating a 2 x 2 matrix to plot the answers to the four key aspects. He arranged the matrix's strengths and weaknesses on the top row and opportunities and threats on the bottom. This is still the most common method of conducting the analysis today. While there are other formats for the Personal SWOT Analysis, the matrix is a four-quadrant table with a color-coded grid in its most basic form. The creators viewed strengths and opportunities as advantageous and under your control, whereas external factors dictate weaknesses and threats.