Volumes of evidence: examining technical change in the last century through a new lens

New indicators of technical change based on titles included in the catalogue of the Library of Congress and on Amazon.com's website are presented along with evidence that they do capture technological innovation. The indicators are used to chart the pattern and nature of technical change over the last century. A strong, causal relationship is found to exist between these indicators and changes in TFP and output per capita. Moreover, innovations in some subgroups have had a greater impact on output and productivity than in others and the key players change over time. Information technologies are currently the dominant subgroup. JEL classificatiion: E32, O3, O4, N1