One session, two tapes: every options NBBO update vs. every stock NBBO update

WITH (
    SELECT max(toDate(toTimeZone(window_start, 'America/New_York')))
    FROM global_markets.delayed_stocks_minute_aggs
    WHERE ticker = 'SPY'
      AND window_start >= toDateTime(today() - 10)
      AND window_start < toDateTime(today() - 4)
) AS session_day,
(
    SELECT (count(), uniqExact(ticker))
    FROM global_markets.cache_stocks_quotes
    WHERE sip_timestamp >= toDateTime(session_day)
      AND sip_timestamp < toDateTime(session_day + 1)
) AS stock_tape,
(
    SELECT (count(), uniqExact(ticker))
    FROM global_markets.options_trades
    WHERE sip_timestamp >= toDateTime(session_day)
      AND sip_timestamp < toDateTime(session_day + 1)
) AS option_trades_t,
(
    SELECT toUInt32(max(sip_timestamp)) - toUInt32(min(sip_timestamp))
    FROM global_markets.cache_options_quotes
    WHERE ticker >= 'O:SPY26' AND ticker < 'O:SPY27'
      AND sip_timestamp >= toDateTime(session_day)
      AND sip_timestamp < toDateTime(session_day + 1)
) AS spy_span_seconds
SELECT
    toString(session_day) AS session_date,
    round(count() / 1e9, 2) AS option_quote_updates_bn,
    round(stock_tape.1 / 1e6, 0) AS stock_quote_updates_m,
    stock_tape.2 AS stock_symbols_quoted,
    round(count() / stock_tape.1, 1) AS option_to_stock_ratio,
    round(option_trades_t.1 / 1e6, 1) AS option_trades_m,
    round(option_trades_t.2 / 1e3, 0) AS option_contracts_traded_k,
    round(count() / option_trades_t.1, 0) AS quote_updates_per_trade,
    round(count() / spy_span_seconds / 1e3, 0) AS avg_updates_per_second_k
FROM global_markets.cache_options_quotes
WHERE sip_timestamp >= toDateTime(session_day)
  AND sip_timestamp < toDateTime(session_day + 1)