NIKA2 is a dual-band millimetric continuum camera of 2900 Kinetic Inductance Detectors (KID), operating at $150$ and $260,rm{GHz}$, installed at the IRAM 30-meter telescope. We present the performance assessment of NIKA2 after one year of observation using a dedicated point-source calibration method, referred to as the emph{baseline} method. Using a large data set acquired between January 2017 and February 2018 that span the whole range of observing elevations and atmospheric conditions encountered at the IRAM 30-m telescope, we test the stability of the performance parameters. We report an instantaneous field of view (FOV) of 6.5 in diameter, filled with an average fraction of $84%$ and $90%$ of valid detectors at $150$ and $260,rm{GHz}$, respectively. The beam pattern is characterized by a FWHM of $17.6 pm 0.1$ and $11.1pm 0.2$, and a beam efficiency of $77% pm 2%$ and $55% pm 3%$ at $150$ and $260,rm{GHz}$, respectively. The rms calibration uncertainties are about $3%$ at $150,rm{GHz}$ and $6%$ at $260,rm{GHz}$. The absolute calibration uncertainties are of $5%$ and the systematic calibration uncertainties evaluated at the IRAM 30-m reference Winter observing conditions are below $1%$ in both channels. The noise equivalent flux density (NEFD) at $150$ and $260,rm{GHz}$ are of $9 pm 1, rm{mJy}cdot s^{1/2}$ and $30 pm 3, rm{mJy}cdot s^{1/2}$. This state-of-the-art performance confers NIKA2 with mapping speeds of $1388 pm 174$ and $111 pm 11 ,rm{arcmin}^2cdot rm{mJy}^{-2}cdot rm{h}^{-1}$ at $150$ and $260,rm{GHz}$. With these unique capabilities of fast dual-band mapping at high (better that 18) angular resolution, NIKA2 is providing an unprecedented view of the millimetre Universe.
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