The total transaction count (for progress estimation) is counted as the known count at the last checkpoint, plus an estimated number per day.

The last checkpoint is now 996 days ago, and its estimated 60000 transactions per day leads to a total estimate of 96M transactions, while the real number is around 183M.

Fix this by updating the count, timestamp, and rate of transactions... with or without adding a new checkpoint.
{
    if (request.fHelp || request.params.size() != 1) {
        throw runtime_error(
            "getmempoolentry txid\n"
            "\nReturns mempool data for given transaction\n"
            "\nArguments:\n"
            "1. \"txid\"                   (string, required) The transaction id (must be in mempool)\n"
            "\nResult:\n"
            "{                           (json object)\n"
            + EntryDescriptionString()
            + "}\n"
            "\nExamples:\n"
            + HelpExampleCli("getmempoolentry", "\"mytxid\"")
            + HelpExampleRpc("getmempoolentry", "\"mytxid\"")
        );
    }
    uint256 hash = ParseHashV(request.params[0], "parameter 1");
    LOCK(mempool.cs);
    CTxMemPool::txiter it = mempool.mapTx.find(hash);
    if (it == mempool.mapTx.end()) {
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction not in mempool");
    }
    const CTxMemPoolEntry &e = *it;
    UniValue info(UniValue::VOBJ);
    entryToJSON(info, e);
    return info;
}
UniValue getblockhash(const JSONRPCRequest& request)