Within Lightcast job postings, we can measure the number of job postings over a given timeframe two different ways.
Newly Posted measures all postings that were posted in that month.
Active measures how many postings were live during that month, even if originally posted in a previous month but left active by the employer. Active postings make use of our expiration methodology described here. Lightcast constantly works to improve our methodology on when postings expire. Improvements, as well as any market change, may cause increases and decreases in our our active postings trend. Our overall tracking of expired postings is more accurate, but as a result trend lines may differ significantly.
Active postings are a good way to get a view of the total open demand present in a given month while Newly Posted gives a better view of the behavior of the market in a given month and over time.