We introduce a minimal two-parameter formulation of the dark energy (DE) density evolution normalized to its present-day value, $f_{\mathrm{DE}}(z)\equiv {\rho }_{\mathrm{DE}}(z)/{\rho }_{\mathrm{DE},0}$, in terms of $f_p\equiv f_{\mathrm{DE}}(z_p)$ and the DE equation of state $w_p\equiv w(z_p)$, at a pivot redshift $z_p$. This provides an alternative framework for assessing the evidence for evolving DE, complementary to the established Chevallier-Polarski-Linder (CPL) parametrization of the DE equation of state in terms of $w_0$ and $w_a$. By parametrizing the DE density directly, the $(w_p,f_p)$ formulation avoids the approximate degeneracies intrinsic to the $(w_0,w_a)$ basis—in particular the weak sensitivity of the expansion history to $w_a$—while reproducing the background evolution of representative thawing quintessence models with equivalent accuracy. Confronting it with the latest baryon acoustic oscillation (BAO) measurements from DESI, a prior on early-Universe parameters from Planck cosmic microwave background (CMB) observations, and Type Ia supernovae (SNe) data, we find that the $w_p$ and $f_p$ parameters are both tightly constrained and sensitive to distinct subsets of the data. Specifically, $w_p$ is measured to percent-level precision by BAO and CMB alone, while $f_p$ is pinned down by the independent matter density constraint that only SNe provide. Including the Pantheon+ SNe sample, we obtain $w_p=-1.04\pm 0.04$ and $f_p=1.07\pm 0.04$, with similar results when using the DESY5 SNe sample. The frequentist preference for evolving DE over $\mathrm{\Lambda }\mathrm{CDM}$ remains below $3\sigma$ across all dataset combinations, comparable to that obtained with CPL. Notably, the proximity of both $w_p$ and $f_p$ to their cosmological constant values of $(-1,1)$—precisely at the epoch where the data are most sensitive—deepens the coincidence previously identified in the CPL framework, reinforcing the case for caution in interpreting the current evidence for dynamical DE.

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• Baryon acoustic oscillations
• Cosmic microwave background
• Cosmological constant
• Cosmological parameters
• Dark energy
• Large scale structure of the Universe