We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor $overline{ u}_{e}$ inverse beta decay candidates observed over 1958 days of data collection. The installation of a Flash-ADC readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic $^9$Li and $^8$He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative $overline{ u}_{e}$ rates and energy spectra among detectors yields $sin^{2}2theta_{13} = 0.0856pm 0.0029$ and $Delta m^2_{32}=(2.471^{+0.068}_{-0.070})times 10^{-3}~mathrm{eV}^2$ assuming the normal hierarchy, and $Delta m^2_{32}=-(2.575^{+0.068}_{-0.070})times 10^{-3}~mathrm{eV}^2$ assuming the inverted hierarchy.
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