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.
CCriticalSection cs_main;
BlockMap mapBlockIndex;
CChain chainActive;
CBlockIndex *pindexBestHeader = NULL;
CWaitableCriticalSection csBestBlock;
CConditionVariable cvBlockChange;
int nScriptCheckThreads = 0;
std::atomic_bool fImporting(false);
bool fReindex = false;
bool fTxIndex = false;
bool fHavePruned = false;
bool fPruneMode = false;
bool fIsBareMultisigStd = DEFAULT_PERMIT_BAREMULTISIG;
bool fRequireStandard = true;
bool fCheckBlockIndex = false;
bool fCheckpointsEnabled = DEFAULT_CHECKPOINTS_ENABLED;
size_t nCoinCacheUsage = 5000 * 300;
uint64_t nPruneTarget = 0;
int64_t nMaxTipAge = DEFAULT_MAX_TIP_AGE;
bool fEnableReplacement = DEFAULT_ENABLE_REPLACEMENT;
CFeeRate minRelayTxFee = CFeeRate(DEFAULT_MIN_RELAY_TX_FEE);
CAmount maxTxFee = DEFAULT_TRANSACTION_MAXFEE;
CTxMemPool mempool(::minRelayTxFee);
static void CheckBlockIndex(const Consensus::Params& consensusParams);
CScript COINBASE_FLAGS;
const string strMessageMagic = "Bitcoin Signed Message:\n";
namespace {
    struct CBlockIndexWorkComparator
    {
        bool operator()(CBlockIndex *pa, CBlockIndex *pb) const {