This study examines diachronic changes in number use in written American English from 1923 to 2008 in TIME magazine, analyzing a 170-million-token corpus. We investigate the effects of magnitudes, roundness, and representational formats on number frequency, along with the evolution of culturally salient numbers reflecting societal shifts. Utilizing Bayesian negative binomial regression for in-depth corpus analysis, our findings demonstrate a consistent influence of magnitudes and roundness, with smaller magnitudes and rounder numbers appearing more frequently. We observe a significant standardization in portraying large numbers, marked by a shift from numerical to mixed forms (e.g., “6,000,000,000” to “6 billion”) around 1940s. This reflects changes in both formal writing conventions and editorial practices of numerical representation. Our research further identifies distinct culturally significant numbers for each decade, linked to social, economic, and technological trends, underscoring the role of numerical analysis in media to decode complex cultural and societal patterns. This study contributes significantly to understanding the dynamic interplay between language, culture, and media in the context of numerical representations.