Fig 3. All fields Likert chart: 5500 respondents.

The number of responses less than zero on the x-axis include almost never (ω₀), sometimes (ω₁) and half of the often (ω₂) responses. The number of responses greater than zero include almost always (ω₄), usually (ω₃), and half of the often responses. The mean scores on the y-axis are $s_i={\Sigma }_1^{n_i}{\omega }_{i,k}/n_i$ and varies from a low of 0.7 (troubleshooting) to a high of 3.7 (drafting).