Nowadays, fostering a dynamic economy focused on innovation is vital. The Global Innovation Index (GII) is considered an effective instrument for assessing and quantifying the innovation-oriented progress of an economy. Along with the majority of upper-middle-income countries, Armenia reported a decline in GII 2022 scores compared to 2018 score values. The research aims to figure out how five-year changes in score values of two sub-indices of the Global Innovation Index (input and output) of countries with an income level comparable to Armenia explained the statistically significant changes in the GII score values over the past five years utilizing least squares estimation technique. The research novelty is that the authors found that if the difference in the input sub-index of an average middle-income country over five years changes by 1%, it can cause a higher difference in score values of the GII index than changes in the output sub-index, other things being equal. The estimation results indicate that the priority for an average middle-income country government should be the design of such initiatives and the adoption of such measures that will contribute to an increase in the score of the sub-indices of input and output pillars of the GII in the medium term, while emphasizing the role of input pillars. The results can be applied by the Ministry of Economy of Armenia, policy and strategy developers, researchers, and independent experts interested in this field.