Back on the first of May, there were fears that the market may have been commencing another downward leg. The ASX plummeted by as much as 5% in one trading session, its largest drop in weeks.

However, amid strong buying volume from retailers investing in stocks, the ASX recorded its second consecutive monthly gain. During May, those gains totalled 4.2%. In fact, each week throughout May saw the local market edge higher.

One of the key trends we witnessed was a rotation of funds through various sectors and high-profile shares. Investment themes predominantly related to tech, mining and in the final week of May, banking.

Here is what the Selfwealth community were buying and selling through their Selfwealth trading accounts during May.

Which shares and ETFs were the most held?

It was an unchanged list of names that occupied the top spots across Selfwealth members' trading accounts throughout May. The collective valuation of each stock across the top 20 most-held shares increased significantly relative to April. In most cases, the valuation increase exceeded 10% for each of the stocks, while the lowest was just 4%.

In light of the banks' significant late-month rally, the Big Four were instrumental in driving portfolio values higher. The value of Commonwealth Bank (ASX: CBA) shares held by Selfwealth members increased 18.8%, but this paled in comparison to the nation other leading bank shares. Investment values in Westpac (ASX: WBC) shares held through Selfwealth trading accounts increased 33.8%, while NAB (ASX: NAB) and ANZ (ASX: ANZ) followed closely with gains of 31.6% and 27.8% respectively.Macquarie Group (ASX: MQG) also recorded similar growth across the community. Selfwealth members who were investing in stocks from the bank industry clearly had exposure to strong performance tailwinds as the S&P/ASX 200 Banks Index (ASX: XBK) surged 12.9% in just one week.As we alluded to earlier, mining shares were also strong beneficiaries of an inflow in funds from those investing in stocks leveraged to iron ore, and to a lesser extent, gold. The value of holdings in BHP (ASX: BHP), Rio Tinto (ASX: RIO) and Fortescue Metals (ASX: FMG) increased 20.6%, 21.1% and 8.2% respectively. There was some irony in this given FMG share price gains throughout May outpaced its peers, climbing 16.2%, versus 7.1% (BHP) and 6.7% (Rio). All three, however, lagged the rise in iron ore, which was closer to 25%.Market darling Afterpay (ASX: APT) was also a prominent sight in the portfolios of numerous Selfwealth members. The company strong trading update helped catapult its shares towards a new all-time high, turning into $50-plus shares. Investment banks have remained a key backer of the buy-now pay-later stalwart, while the addition of Tencent to the company share register was received well. The value of APT shares across all Selfwealth portfolios increased by 31.2%, which was less than its 50%+ rise.StockCompany1CSLCSL Limited2CBACommonwealth Bank3WBCWestpac4NABNational Australia Bank5AFIAustralian Foundation Inv6ANZAustralia and New Zealand Banking Group7BHPBHP8MQGMacquarie Group9SWFSelfwealth10TLSTelstra11NEUNeuren Pharmaceuticals12APTAfterpay13ARGArgo Investments14WPLWoodside Petroleum15WESWesfarmers16MLTMilton Corp17WOWWoolworths18RIORio Tinto19FMGFortescue Metals Group20COHCochlearThe value of shares held in the Vanguard Australian Shares Index ETF (ASX: VAS) jumped 19.2%, with capital flowing in line with the trend that saw the ASX post solid monthly gains.The other clear winner was the Betashares NASDAQ 100 ETF (ASX: NDQ). Given the strong performance of the NASDAQ following its low in March, a high number of Selfwealth members have been investing in stocks offering exposure to the FANG companies. The Nasdaq 100 ETF is considered one conduit for this. The value of NDQ shares skyrocketed 33.7% month-over-month.As a risk-off mentality returned to the market, the previously-high increase in funds directed towards the Australian High Interest Cash ETF (ASX: AAA) were stripped out. The value of funds held in the ETF declined 24.5% during May, with more individuals investing in stocks in lieu of holding cash.ETFCompany1VASVanguard Australian Shares Index ETF2VDHGVanguard Diversified High Growth Index ETF3VGSVanguard MSCI Index International Shares ETF4VTSVanguard U.S. Total Market Shares Index ETF5A200BetaShares Australia 200 ETF6IVVIshares S&P 500 ETF7VEUVanguard All-World ex-U.S. Shares Index ETF8NDQBetashares Nasdaq 100 ETF9AAAAAA Australian High Interest Cash ETF10STWSPDR S&P/ASX 200 Fund

Which shares and ETFs were the most traded?

Buyers remained firmly in control last month, with the surplus of buying volume to selling volume increasing to a five-month high. Much of this strength came from outside the top 10 most-bought stocks, which also aligns with a large extent of the market recent gains.

PurchasesCodeSecurity1BBOZBetashares Australian Equities Strong Bear Hedge Fund2VASVanguard Australian Shares Index ETF3CBACommonwealth Bank4CSLCSL5WBCWestpac6GEARBetashares Geared Australian Equity Fund7ANZANZ8MQGMacquarie Group9BBUSBBUS U.S Equities Strong Bear Fund10APTAfterpay

SalesCodeSecurity1BBOZBetashares Australian Equities Strong Bear Hedge Fund2CBACommonwealth Bank3APTAfterpay4GEARBetashares Geared Australian Equity Fund5WBCWestpac6ANZANZ7FMGFortescue Metals Group8BBUSBBUS U.S Equities Strong Bear Fund9MQGMacquarie Group10CSLCSL

While leveraged ETFs remain a popular trading option, the value associated with their trades diminished quite significantly during May. The value of buy orders for the Australian Equities Strong Bear Fund (ASX: BBOZ) decreased 29.9% compared with April, while its US-oriented peer, the U.S Equities Strong Bear Fund (ASX: BBUS), saw a 28% decline.It wasn't just bearish ETFs where interest dried up, however, as the value of buy orders for the Betashares Geared Australian Equity Fund (ASX: GEAR) slumped 23%. On the other side of the equation, sell activity for these ETFs also decreased by a wide margin, suggesting that those investing in stocks like BBOZ and GEAR are potentially holding them longer than the last batch of holders, as opposed to trading them.As we touched on earlier, heavy funds were directed towards the banks, as well as popular favourites like Afterpay and CSL (ASX: CSL). Despite the biotechnology giant share price falling 10.7% across May, there was no increase in selling activity among Selfwealth members. In fact, the value of CSL sell orders diminished around 6%, while the value of buy orders jumped 30%.Elsewhere, Selfwealth members showed that they were keen to continue investing in stocks related to the travel industry. Webjet (ASX: WEB), Qantas (ASX: QAN) and Flight Centre (ASX: FLT) were the third, fourth and fifth most-bought stocks in terms of order numbers, totalling more than 5,000 orders. Sell orders for these stocks were also above-average, but still about only one-third that of buy orders. Southern Cross Media Group (ASX: SXL) was another trading favourite for the month, with nearly 1,200 buy orders placed as investors began to speculate on a turnaround.

That all for this Trade Trends report, stay tuned for the next edition this time next month!