We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor <math><msub><mover><mi>ν</mi><mo>¯</mo></mover><mi>e</mi></msub></math> inverse <math><mi>β</mi></math> decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter 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 <math><mrow><mmultiscripts><mrow><mi>Li</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>9</mn></mrow></mmultiscripts></mrow></math> and <math><mrow><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> 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 <math><msub><mover><mi>ν</mi><mo>¯</mo></mover><mi>e</mi></msub></math> rates and energy spectra among detectors yields <math><mrow><msup><mrow><mi>sin</mi></mrow><mrow><mn>2</mn></mrow></msup><mn>2</mn><msub><mrow><mi>θ</mi></mrow><mrow><mn>13</mn></mrow></msub><mo>=</mo><mn>0.0856</mn><mo>±</mo><mn>0.0029</mn></mrow></math> and <math><mrow><mi>Δ</mi><msubsup><mrow><mi>m</mi></mrow><mrow><mn>32</mn></mrow><mrow><mn>2</mn></mrow></msubsup><mo>=</mo><mo>(</mo><msubsup><mrow><mn>2.471</mn></mrow><mrow><mo>−</mo><mn>0.070</mn></mrow><mrow><mo>+</mo><mn>0.068</mn></mrow></msubsup><mo>)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>eV</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> assuming the normal hierarchy, and <math><mrow><mi>Δ</mi><msubsup><mrow><mi>m</mi></mrow><mrow><mn>32</mn></mrow><mrow><mn>2</mn></mrow></msubsup><mo>=</mo><mo>−</mo><mo>(</mo><msubsup><mrow><mn>2.575</mn></mrow><mrow><mo>−</mo><mn>0.070</mn></mrow><mrow><mo>+</mo><mn>0.068</mn></mrow></msubsup><mo>)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>eV</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> assuming the inverted hierarchy.

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