; and of which not less than $68,950,000 shall be for the Division of Economic and Risk Analysis: In addition, for costs associated with relocation under a replacement lease for the Commission’s headquarters facilities, not to exceed $244,507,000, to remain available until September 30, 2019. For purposes of calculating the fee rate under section 31(j) of the Securities Exchange Act of 1934 ( 15 U.S.C. 78ee(j) ) for fiscal year 2018, all amounts appropriated under this heading shall be deemed to be the regular appropriation to the Commission for fiscal year 2018. Provided , That fees and charges authorized by section 31 of the Securities Exchange Act of 1934 ( 15 U.S.C. 78ee ) shall be credited to this account as offsetting collections: Provided further , That not to exceed $1,652,000,000 of such offsetting collections shall be available until expended for necessary expenses of this account and not to exceed $244,507,000 of such offsetting collections shall be available until September 30, 2019, for costs under this heading associated with relocation under a replacement lease for the Commission’s headquarters facilities: Provided further , That the total amount appropriated under this heading from the general fund for fiscal year 2018 shall be reduced as such offsetting fees are received so as to result in a final total fiscal year 2018 appropriation from the general fund estimated at not more than $0: Provided further , That if any amount of the appropriation under this heading for costs associated with relocation under a replacement lease for the Commission’s headquarters facilities is subsequently de-obligated on or before September 30, 2019, any such amount derived from the general fund shall be returned to the general fund, and any such amount derived from fees or assessments collected for such purpose shall be paid to each national securities exchange and national securities association, respectively, in proportion to any fees or assessments paid by such national securities exchange or national securities