To answer your question accurately regarding the actual population numbers shown on page 13 of "The Future of Life on Earth" Express edition by Michael Bright, you would typically need to refer to the graph in the book. However, generally speaking, actual population data is often available until a certain year after which projections or estimates are made.
In many demographic studies, historical population data is available up to around 1950-2000, depending on the source. It would be reasonable to deduce that the years during which actual population numbers were shown are typically from the earliest point of recording (often around 1800) up to the most recent year before projections begin.
Based on this reasoning, the best answer would likely be 1950-2005 unless the graph indicates otherwise. Please check the graph from the book to confirm the years of actual data.