SPY fell by 4.7% this week, while my account rose 0.9%. I am out of the market again; many pundits believe that next Monday will bring either a large bounce or a crash.
This week, I have changed the “Daily % Gain” table so all figures are percentages of my total account, not of the individual trade. Basically, all numbers are now ⅟₇ of what they used to be. This removes the disparity between the daily table above and the robot’s weekly table below, which was already using total-account figures.
|Buy date||Buy price||Sell date||Sell price||Acct Profit|
|TZA#1||MA 14 11:00||(Skipped)||$20.58||(Not yet)|
|SRTY#1||MA 14 12:00||MA 14 11:00||$51.05||$51.25||MA 09 14:00||$50.57||$50.50||-0.2%|
|SRTY#2||MA 16 10:00||$50.75||$50.58||MA 18 11:00||$55.75||$55.70||+1.3%||+1.4%|
|SRTY#3||MA 18 12:00||$57.52||$57.50||MA 18 13:00||$56.47||$56.46||-0.3%|
TZA#1: Argh! The robot didn’t buy because it got an IWM real-time quote from Schwab at 11am that was higher than the one for 10am, while stockcharts.com shows a lower price. Because of the new STDDEV rule, the robot then refused to buy TZA all week, waiting for a bounce that never came. As I suspected last week, it was a bad idea to sell TZA last Thursday and it might well turn out to have been a bad idea not to overrule the robot and buy TZA this week.
SRTY: This ticker underwent a 1-for-5 reverse split last Friday, so all price-quotes are now five times larger ($50 instead of $10).
SRTY#2: Good timing on the purchase! The robot shorted the market on Wednesday at what turned out to be nearly the highest price of the day. Friday’s sale-time wasn’t so hot, though.
SRTY#3: This was stupid. I have added a new rule: Do not buy SRTY unless at least two hours have passed since the last sale. This rule increases average profit slightly (from 10.4%/year to 10.5%/year) and improves the win:loss ratio slightly (from 101:118 to 101:116 since 2008) but the main point is that it would have blocked the third trade this week.
Daily stop-update: Friday’s stop price for SRTY#2 should have been $50.40 (for a -0.1% max loss) but the robot chose $49.48 (for -0.3%). As a result, the max-loss actually went *down* from Thursday’s -0.2%. I really ought to fix this, by fetching quotes for IWM and SRTY during the same invocation of Opera so their prices will differ by milliseconds instead of seconds.