Table of current RRRs for many countries at Central Bank News here. (Try to just ignore the common reification error of "lend out the reserves!" these people typically make here for now...)
TURKEY Central Bank of Republic of Turkey 16-Feb-19 7.00% 8.00%
UNITED STATES 1) Federal Reserve 27-Oct-16 3.00%
URUGUAY Central Bank of Uruguay 1-Apr-13 25.00% 20.00%
UZBEKISTAN Central Bank of the Rep. Of Uzbekistan 1-Sep-09 15.00%
VENEZUELA Central Bank of Venezuela 25-Oct-13 19.00% 17.00%
U.S. listed at 3% , based on system level (H.8) Deposit Liabilities of $12T that 3% would put required system level reserves at about $360B;
Meanwhile latest H.4.1 from the Fed has total system reserves at $3.900T and those of Federal Reserve Banks at about $1.544T; the rest being in currency, TGA and other non-Reserve Bank accounts...
So its hard to understand how any significant demand for Reserve balances could be being caused by the Reserve Requirement Ratio as the system has up to over 10x the minimum mandated by the RRR... current Reserve demand, if there effectively really is any, is being caused by functional regulatory policy(s) other than the RRR.
So I don't see why anyone would want to always be dogmatically stressing the functionality of Reserve demand to meet the RRR in their Theory all the time these days... doesnt seem applicable for the last 10 years or more... ever since added system Reserves went asymtotic in September 2008 and caused the crash...