# The cost of idle AI capex is a lag problem, not a rate problem
Latent Equity · published Oct 22, 2026 · AI capital ledger
Post: https://x.com/Latent_Equity/status/2113275776221012344

Our read: the cost of AI capex sitting idle is a $10–20B-a-year problem, not a rate problem (our scenario).

Start with the run-rate. $AMZN, $GOOGL, $META, $MSFT and $ORCL spent about $65.8B a month on capex in their latest quarters, $META's being Q3 from its release (our calc). That is total capex; none of them splits out AI.

Now add a lag. Gear that is bought but not yet earning, for 3 to 6 months, means $197–395B sitting idle at any time (our scenario).

$NVDA's Jensen Huang put it at "a few hundred billion dollars sitting idle." Our range brackets his.

The carrying cost: at a 5.1–5.6% weighted average coupon on their existing debt (our calc; $MSFT uses the five-company average as a proxy), that idle pile costs about $10.4B a year at a 3-month lag and $20.7B at 6 months (our scenario, pre-tax). Cutting the lag from 6 months to 1 saves ~$17.3B a year, about 3 points of interest cost on ~$545B of debt (our calc; no offset for interest income on cash).

So the number to watch is how fast new capacity gets switched on, more than where rates go.

The live meter: construction in progress (spending not yet in service) as a share of gross property and equipment (our calc):
$META 15.3% (mid-2024) → 27.4% (Sep 2026), flat since June
$GOOGL 20.2% (end-2024) → 28.8% (mid-2026)
$ORCL 16.2% (May 2024) → 32.6% (May 2026), 31.6% (Aug 2026)

Which do you watch more closely: the lag or the rate?

What would prove us wrong:
- That share turns down at $META and $GOOGL and keeps falling at $ORCL (it eased to 31.6% in Aug from 32.6% in May), in the next 10-Qs. Not tripped: $GOOGL is still climbing and $META held flat at 27.4% in Q3.

General research, the same for every reader. Not investment advice.