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.
class CBlockTreeDB;
class CBloomFilter;
class CChainParams;
class CInv;
class CConnman;
class CScriptCheck;
class CTxMemPool;
class CValidationInterface;
class CValidationState;
struct ChainTxData;
struct PrecomputedTransactionData;
struct LockPoints;
static const bool DEFAULT_WHITELISTRELAY = true;
static const bool DEFAULT_WHITELISTFORCERELAY = true;
static const unsigned int DEFAULT_MIN_RELAY_TX_FEE = 1000;
static const CAmount DEFAULT_TRANSACTION_MAXFEE = 0.1 * COIN;
static const CAmount HIGH_TX_FEE_PER_KB = 0.01 * COIN;
static const CAmount HIGH_MAX_TX_FEE = 100 * HIGH_TX_FEE_PER_KB;
static const unsigned int DEFAULT_MAX_ORPHAN_TRANSACTIONS = 100;
static const int64_t ORPHAN_TX_EXPIRE_TIME = 20 * 60;
static const int64_t ORPHAN_TX_EXPIRE_INTERVAL = 5 * 60;
static const unsigned int DEFAULT_ANCESTOR_LIMIT = 25;
static const unsigned int DEFAULT_ANCESTOR_SIZE_LIMIT = 101;
static const unsigned int DEFAULT_DESCENDANT_LIMIT = 25;
static const unsigned int DEFAULT_DESCENDANT_SIZE_LIMIT = 101;
static const unsigned int DEFAULT_MEMPOOL_EXPIRY = 72;
static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; 
static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; 
static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; 
static const int MAX_SCRIPTCHECK_THREADS = 16;