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We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete sample of 33 TDEs is constructed using the Zwicky Transient Facility over 3 yr (from 2018 October to 2021 September). We infer the black hole (BH) mass ( M _BH ) with host galaxy scaling relations, showing that the sample M _BH ranges from 10 ^5.1 M _⊙ to 10 ^8.2 M _⊙ . We developed a survey efficiency corrected maximum volume method to infer the rates. The rest-frame g -band luminosity function can be well described by a broken power law of $\phi ({L}_{g})\propto {\left[{\left({L}_{g}/{L}_{\mathrm{bk}}\right)}^{0.3}+{\left({L}_{g}/{L}_{\mathrm{bk}}\right)}^{2.6}\right]}^{-1}$ , with L _bk = 10 ^43.1 erg s ^−1 . In the BH mass regime of 10 ^5.3 ≲ ( M _BH / M _⊙ ) ≲ 10 ^7.3 , the TDE mass function follows $\phi ({M}_{\mathrm{BH}})\propto {M}_{\mathrm{BH}}^{-0.25}$ , which favors a flat local BH mass function ( ${{dn}}_{\mathrm{BH}}/d\mathrm{log}{M}_{\mathrm{BH}}\approx \mathrm{constant}$ ). We confirm the significant rate suppression at the high-mass end ( M _BH ≳ 10 ^7.5 M _⊙ ), which is consistent with theoretical predictions considering direct capture of hydrogen-burning stars by the event horizon. At a host galaxy mass of M _gal ∼ 10 ^10 M _⊙ , the average optical TDE rate is ≈3.2 × 10 ^−5 galaxy ^−1 yr ^−1 . We constrain the optical TDE rate to be [3.7, 7.4, and 1.6] × 10 ^−5 galaxy ^−1 yr ^−1 in galaxies with red, green, and blue colors.