Growth of Digital Marketing Expenditure and Online Consumer Engagement in India: Evidence from Industry Reports, 2010–2025

This paper explores the sociocultural history of the Indian digital advertising sector as well as the relationship between the continued digital spending and aggregate consumer engagement on the web between 2010 and 2025. The study incorporates digital spending, engagement metrics, and infrastructure indicators in an annual macro-panel based on a consolidated longitudinal dataset of multi-source industry evidence, consisting of GroupM, Dentsu, IAMAI-Kantar, CRISIL, Ipsos, Nielsen and statista, databases. Elasticity-based regression analysis and trend diagnostics demonstrate that there are three growth stages, including early diffusion (2010-2014), mobile-first acceleration (2015-2019), and post-pandemic maturity (2020-2025). Digital investments broadened almost forty-fold, and impressions increased in the same line and click-throughs decreased and video view rates increased, indicating that there is a difference in engagement trends across the different formats. The results of econometric estimates serve to substantiate an increase in impressions and video completion with a simultaneous rise in expenditure and user-base, and a negative elasticity of CTR in ecosystem saturation. Breaks in 2016 and 2020 are structural changes, which reflect big access and behavioural jolts that change the dynamics of engagement. The research provides one of the earliest, country-specific, longer-period studies of relationships of spending and engagement that shows that infrastructural changes and ecosystem-level inflexions drive digital advertising performance even more successfully than incremental spending. The implication is on market strategy, standardisation of measurements, and way of designing policies in maturing digital economies.