Long time readers will know this is about the 678,211,121st (give or take) time I've cut back the fertilizer names as they break support at the 50 day moving average, only to reverse on me within days. [Jul 7: Cutting Some Fertilizer Exposure] I even wrote in that entryHistorically you want to buy them when they touch the 50 day moving average since they bounce, but with the market acting so poorly we could get some washout action.So ONCE AGAIN - I am repeating the same pattern, and with egg on face buying back what I sold - luckily I sold right near support so we are paying almost the same price to get the position back. It would of been nice to of bought on yesterday mornings dip but I was greedy ...

Simple arithmetic charts are OK for short-term performance review, but can be misleading for long-term purposes. Semi-log charts are best for long-term perspective.

Arithmetic charts space each Dollar move equally on the vertical Y-axis. Semi-log charts space each percentage move equally on the vertical Y-axis. Either method creates only minor differences for short-term charts, but dramatic differences over the long-term, particularly if the security is strongly trending.

The following charts of MSCI emerging market indices illustrate the point. They show 15+ years of gross performance (price plus all dividends) for the emerging market index (proxies: EEM, VWO), India (proxy: INP), China (proxy: FXI), Brazil (proxy: EWZ), Russia (proxy: RSX) and Mexico (proxy EWW).

The semi-log format (called “semi” because the X-axis remains arithmetic with equal spaces between dates) gives a truer picture of trend.  A constant rate of change on

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