Growth-Trend Timing — Industrial Production (INDPRO)
Developed by Philosophical Economics · Macro + Trend · Low Risk
Growth-Trend Timing using industrial production data was developed by the anonymous author of the Philosophical Economics blog, one of the most intellectually rigorous finance blogs of the 2010s. The strategy applies a fundamentally different approach to tactical allocation: rather than using price-based momentum or trend signals, it uses real economic data — specifically, the Federal Reserve's Industrial Production Index (INDPRO) — to determine whether the economy is in an expansion or contraction phase, and positions the portfolio accordingly.
The theoretical foundation is straightforward. Equity markets are ultimately driven by corporate earnings, which are closely linked to industrial output. When industrial production is growing, corporate revenues and profits tend to expand, supporting higher equity valuations. When industrial production contracts, earnings decline and equity markets typically follow. By positioning in equities during expansion phases and in bonds during contractions, the strategy aims to capture the majority of equity upside while avoiding the recessions that produce the deepest drawdowns.
The strategy uses a binary allocation model: 100% in US equities (SPY) when the industrial production trend is positive, 100% in intermediate bonds (IEF) when it is negative. The trend determination uses the year-over-year change in the seasonally adjusted industrial production index — a smoothed measure that filters out monthly noise while remaining responsive to genuine shifts in economic activity. When year-over-year industrial production growth turns negative, the strategy exits equities; when it recovers, the strategy re-enters.
The use of macroeconomic data rather than price data gives GTT-INDPRO a fundamentally different signal character from momentum-based strategies. Price momentum can generate false signals from temporary market reactions to news events, sentiment shifts, or technical factors. Industrial production, as a measure of real economic output, reflects underlying business conditions that are less susceptible to speculative noise. The trade-off is latency: economic data is released with a lag of several weeks after the measurement period, and the trends themselves evolve more slowly than market prices. This means the strategy enters and exits positions later than price-based alternatives, but its signals tend to be more reliable indicators of sustained economic regime changes.
How It Works
The Industrial Production Signal
Each month, following the Federal Reserve's release of the Industrial Production Index (INDPRO), the strategy evaluates whether the year-over-year change in the seasonally adjusted index is positive or negative. A positive year-over-year change indicates that the economy is producing more goods than it was twelve months ago — an expansion signal. A negative change indicates contraction.
The year-over-year comparison rather than month-over-month smooths out seasonal fluctuations and short-term production disruptions, providing a cleaner read on the underlying economic trend. The INDPRO index covers manufacturing, mining, and utilities output, representing a broad cross-section of the industrial economy that historically correlates strongly with aggregate corporate earnings growth.
Binary Allocation
When year-over-year industrial production growth is positive, the portfolio holds 100% US equities (SPY). When it turns negative, the portfolio shifts entirely to intermediate bonds (IEF). This binary positioning maximizes exposure to equity returns during confirmed economic expansions while providing full protection through bond allocation during contractions.
The simplicity of the decision rule — a single binary reading of one economic indicator — makes the strategy among the easiest to implement and monitor. There are no rankings, no multi-factor composites, no optimization steps. The investor checks one publicly available data point, makes one allocation decision, and waits until the next month's release.
Macro-Based Signal Characteristics
Industrial production trends tend to persist for extended periods — expansions typically last three to seven years, contractions typically last six to eighteen months. This means the strategy generates very few transitions over a full market cycle, producing near-zero turnover during normal conditions. The rare transitions that do occur represent genuine economic regime changes with substantial implications for equity market returns.
The primary trade-off is timing lag. Industrial production data is released approximately six weeks after the measurement period. Combined with the year-over-year smoothing, the signal can take several months to confirm a recession that price-based indicators might have detected earlier. This means the strategy may absorb the initial phase of an equity decline before the macro signal confirms the downturn. However, the same lag also prevents premature re-entry during bear market rallies, keeping the portfolio defensively positioned until the economic recovery is confirmed by real output data.
Explore Growth-Trend Timing — Industrial Production (INDPRO)
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