How many proviso are there to Section 92 of Evidence Act?

There are 6 proviso in Section 92 of Evidence Act Section 92 reads as - Exclusion of evidence of oral agreement. –– When the terms of any such contract, grant or other disposition of property, or any matter required by law to be reduced to the form of a document, have been proved according to the last section, no evidence of any oral agreement or statement shall be admitted, as between the parties to any such instrument or their representatives in interest, for the purpose of contradicting, varying, adding to, or subtracting from, its terms. Proviso(s) I.              Fact which can invalidate any document or entitle any person to any decree or order; like fraud, intimidation, illegality, want of due execution, want of capacity in any contracting party, want or failure of consideration, or mistake in fact or law. II.            Separate oral agreement on matter where the document is silent or which is not inconsistent with its terms III.           Separate oral agreement constituting a condition precedent to attaching any obligation IV.          Subsequent oral agreement to rescind or modify V.            Any usage or custom by which incidents not expressly mentioned in any contract are usually annexed to contracts of that description, may be proved VI.          Any fact may be proved which shows in what manner the language of a document is related to existing facts