Recent observations hint at possible late-time deviations from $\mathrm{\Lambda }$ cold dark matter ($\mathrm{\Lambda }\mathrm{CDM}$) paradigm. We introduce a minimal phenomenological framework in which the total equation of state $w_{\mathrm{T}}(z)$ follows a logistic evolution motivated by renormalization-group-like flow between cosmological fixed points. Using the baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument data release 2, Dark Energy Survey supernova data, and cosmic microwave background distance priors, we find that this parametrization provides an improved description of the expansion history relative to $\mathrm{\Lambda }\mathrm{CDM}$. The reconstructed evolution, though model specific, also shows statistically strong low redshift deviations from $\mathrm{\Lambda }\mathrm{CDM}$.

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• Cosmological parameters
• Cosmology
• Dark energy
• Evolution of the Universe